A pulsed high magnetic field based impact load test platform

Abstract

This invention provides an impact load testing platform based on a pulsed strong magnetic field, belonging to the field of mechanical testing. It includes an impact unit and a power unit. The impact unit is used to fix the test piece and apply a load to it. The power unit provides power to the impact unit to apply the load, and includes an eddy current generating module and a magnetic field regulating module respectively located above and below the impact unit. The eddy current generating module includes an AC conductive coil for connecting to an AC transformer power supply to induce eddy currents in the impact unit. The magnetic field regulating module includes a DC conductive coil for connecting to a DC power supply to form a vertically upward magnetic field. This invention can precisely control the loading rate and load magnitude of the impact unit, realizing multiple loading methods such as quasi-static loading, load function loading, and pulse loading. The load application methods are more diverse and precise, and it has advantages such as simple structure, short manufacturing cycle, environmental friendliness, and low maintenance cost.

Description

Technical Field

[0001] This invention belongs to the field of mechanical testing, and more specifically, relates to an impact load testing platform based on a pulsed strong magnetic field. Background Technology

[0002] In recent decades, the increasing demand for high-response, high-precision, high-power-to-weight ratio, and high-power hydraulic control systems in many industrial sectors and technological fields has spurred the rapid development of hydraulic control technology. Currently, hydraulic control technology is widely used in metallurgy, machinery, transportation (aircraft, shipbuilding, etc.), aerospace, marine technology, modern scientific experiments, and weapons control. In particular, the application of control theory in hydraulic systems and the integration of computer electronics with hydraulic technology have made this technology increasingly sophisticated and mature in terms of components and systems, theory and application, establishing it as a discipline and becoming one of the important development directions of hydraulic technology.

[0003] However, at present, hydraulic servo systems can only be loaded by displacement control and force control when testing the mechanical properties of structures. Due to their precise structure and power limitations, they cannot achieve instantaneous loading and load function loading. Furthermore, the system has disadvantages such as the hydraulic oil being easily contaminated, the high cost of hydraulic servo systems, and the need for high technology for system adjustment and maintenance, which bring many limitations and adverse effects to the conduct of engineering tests. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the purpose of this invention is to provide an impact load test platform based on a pulsed strong magnetic field, which aims to solve the problem that the existing hydraulic loading method cannot achieve load-carrying with the force and load-function loading.

[0005] To achieve the above objectives, the present invention provides an impact load testing platform based on a pulsed strong magnetic field. This platform includes an impact unit and a power unit. The impact unit is used to fix the test piece and apply a load to it. The power unit provides power to the impact unit to apply the load, and includes an eddy current generating module and a magnetic field regulating module respectively disposed above and below the impact unit. The eddy current generating module includes an AC conductive coil for connecting to an AC transformer power supply to induce eddy currents in the impact unit. The magnetic field regulating module includes a DC conductive coil for connecting to a DC power supply to form a vertically upward magnetic field, causing the impact unit to generate a downward electromagnetic force under the action of the eddy currents and the magnetic field, thereby providing power to apply the load.

[0006] As a further preferred embodiment, the eddy current generating module includes a housing and multiple sets of AC conductive coils disposed inside the housing. The AC conductive coils are connected end to end to form circular closed loops of different diameters and are spaced apart from the inside to the outside.

[0007] As a further preferred embodiment, the eddy current generating module further includes multiple partitions, each of which is placed horizontally at a distance in the vertical direction, and each partition is provided with multiple sets of AC conductive coils at intervals from the inside to the outside.

[0008] As a further preferred embodiment, the bottom of the housing is provided with an ear plate for fixed connection with the impact unit.

[0009] As a further preferred embodiment, the magnetic field adjustment module includes a winding core and multiple sets of DC conductive coils. The winding core is a column structure with a stepped body. The DC conductive coils are wound on each step of the winding core and connected end to end to form a circular closed loop with different diameters.

[0010] As a further preferred embodiment, the impact unit includes a panel, a test platform, a support column, and a ballast module, wherein the panel and the test platform are respectively fixed at the upper and lower ends of the support column, the panel is used to fix the eddy current generating module, the test platform is used to fix the test piece, and the magnetic field adjustment module is disposed below the test platform; the ballast module is slidably connected to the support column.

[0011] As a further preferred embodiment, the ballast module includes a ballast plate, a connector, and a lifting rod. The ballast plate is made of metal and is used to induce eddy currents and generate electromagnetic force under the action of a magnetic field. The ballast plate is connected to the lifting rod through the connector. The lifting rod is slidably connected to the support column.

[0012] As a further preferred embodiment, the support column has a sliding groove inside, the fixed end of the lifting rod is connected to the panel, and its movable end is embedded in the sliding groove to slide up and down along the support column.

[0013] As a further preferred embodiment, the test platform, connectors, lifting rods, and support columns are all made of insulating material.

[0014] As a further preferred embodiment, the impact load test platform also includes a tension / compression sensor, which is connected to the test piece.

[0015] In summary, the technical solutions conceived by this invention have the following beneficial effects compared with the prior art:

[0016] 1. This invention utilizes an AC conductive coil connected to an AC transformer power supply to induce eddy currents in the impact unit, while a DC conductive coil connected to a DC power supply forms an upward-emitting magnetic field. According to the principle of electromagnetic induction, the eddy currents and the magnetic field interact to generate a downward electromagnetic force, thereby providing power for applying a load to the impact unit. By adjusting the number of closed circuits in the AC conductive coil and the circuit current intensity of the DC conductive coil, the loading rate and load size of the impact unit can be precisely controlled, realizing various loading methods such as quasi-static loading, load function loading, and pulse loading. Compared with the traditional MTS hydraulic servo loading system, the load application methods are more diverse and precise, and it has advantages such as simple structure, short manufacturing cycle, environmental friendliness, and low maintenance cost.

[0017] 2. In particular, by optimizing the structure of the eddy current generating module, the present invention can make the eddy current density distribution on the ballast plate more uniform by setting AC conductive coils of different diameters at intervals from the inside to the outside on the partition plate and by adjusting the voltage of the AC transformer power supply, thereby reducing the stress concentration of the ballast plate and preventing deformation of the ballast plate. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the impact load test platform based on a pulsed strong magnetic field provided in an embodiment of the present invention;

[0019] Figure 2 This is a cross-sectional view of the impact load test platform based on a pulsed strong magnetic field provided in an embodiment of the present invention;

[0020] Figure 3 This is a schematic diagram of the ballast module structure in the impact load testing platform provided in this embodiment of the invention;

[0021] Figure 4 This is a cross-sectional view of the eddy current generating module in the impact load test platform provided in this embodiment of the invention;

[0022] Figure 5 This is a cross-sectional view of the magnetic field adjustment module in the impact load test platform provided in this embodiment of the invention;

[0023] Figure 6 This is a schematic diagram of the eddy currents induced on the ballast plate 31 by the eddy current generating module provided in this embodiment of the invention.

[0024] In all the accompanying drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0025] 1-Eddy current generating module, 11-Box, 12-Baffle, 13-AC conductive coil, 2-Magnetic field adjustment module, 21-Winding core column, 22-DC conductive coil, 3-Ballast module, 31-Ballast plate, 32-Lifting rod, 33-Connector, 4-Support column, 5-Test platform, 6-Panel, 7-Slide groove, 8-Test piece, 9-Ear plate, 10-Tension and compression sensor. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0027] like Figure 1 , 2 As shown, the present invention provides an impact load test platform based on a pulsed strong magnetic field. The impact load test platform includes an impact unit and a power unit, wherein the impact unit is used to fix the test piece 8 and apply a load to it.

[0028] The power unit is used to provide power for applying load to the impact unit. It includes an eddy current generating module 1 and a magnetic field regulating module 2 respectively disposed above and below the impact unit. The eddy current generating module 1 includes an AC conductive coil 13 for connecting to an AC transformer power supply to form an AC circuit and induce eddy currents in the impact unit.

[0029] The magnetic field adjustment module 2 includes a DC conductive coil 22 for connection to a DC power supply and a resistor to form a DC circuit and a vertically upward magnetic field, so that the impact unit generates a downward electromagnetic force under the action of eddy currents and magnetic field, thereby providing power for applying load to it.

[0030] By using AC and DC circuits as the energy source for platform operation, it features cleanliness and environmental friendliness, and has advantages such as simple experimental device structure, short manufacturing cycle, and low manufacturing and maintenance costs. Furthermore, by adjusting the number of closed AC circuits and the current intensity of DC circuits, the loading mode of the impact unit can be controlled to achieve various loading modes such as quasi-static loading, pulse loading, and load function loading, which facilitates the study of the mechanical properties of the component under test under different loads.

[0031] Furthermore, the impact unit includes a panel 6, a test platform 5, a support column 4, and a ballast module 3. The panel 6 and the test platform 5 are fixed to the upper and lower ends of the support column 4, respectively. The panel 6 is used to fix the eddy current generating module 1, and the test platform 5 is used to fix the test piece 8. At the same time, the four corners of the test platform 5 are lifted by pressure blocks, so that the magnetic field adjustment module 2 is positioned directly below the test platform 5. The ballast module 3 is slidably connected to the support column 4 and includes a ballast plate 31, a connector 33, and a lifting rod 32. The ballast plate 31 is made of metal and is used to generate eddy currents and produce electromagnetic force under the action of a magnetic field. The ballast plate 31 is connected to the lifting rod 32 through the connector 33 to ensure that the ballast plate 31 is in a horizontal state. The support column 4 has a sliding groove 7 inside. The lifting rod 32 is a multi-section lifting rod structure, which uses the relative movement between the segments to achieve lifting. The fixed end of the lifting rod 32 is connected to the panel 6, and its movable end is embedded in the sliding groove 7 to slide up and down along the support rod 4. The frictional resistance between the chute 7 and the lifting rod 32 is small, so as to increase the mechanical efficiency of the ballast plate 31 in loading work.

[0032] Furthermore, the eddy current generating module 1 includes a housing 11 and multiple sets of AC conductive coils 13 disposed inside the housing 11. The AC conductive coils 13 are connected end to end to form circular closed loops of different diameters and are spaced apart from the inside to the outside. During operation, the AC conductive coils 13 are connected to an AC transformer power supply to form an alternating current loop. During the energizing process, the AC transformer power supply changes over time. Since the resistivity of the AC conductive coils 13 remains constant, the current magnitude will change according to the voltage change trend. According to the principle of electromagnetic induction, eddy currents will be induced on the surface of the metal ballast plate 31. Due to the time-varying magnetic induction intensity B generated in the AC transformer circuit, the magnetic flux Φ passing through the ballast plate will change accordingly. Therefore, an induced electromotive force E will be generated on the ballast plate 31, which is affected by the number of turns of the energized coil and the magnitude of the current intensity, thereby ensuring the continuous generation of eddy currents in the ballast plate 31. The relevant theoretical formulas are as follows:

[0033] Φ=B·S

[0034]

[0035]

[0036] In the formula, N is the number of turns of the induction coil, t is time, I is current, and R is resistance.

[0037] The eddy currents generated by eddy current generating module 1 are unevenly distributed on ballast plate 31, such as... Figure 6As shown, this results in a significant difference in electromagnetic force within the region from the center of the ballast plate 31 to the outer diameter of the AC conductive coil 13, and the radial eddy current distribution on the surface of the ballast plate 31 redistributes according to the ballast direction and loading speed. To further reduce the impact of uneven eddy current distribution on the test results, multiple sets of AC conductive coils 13 with diameters r are arranged in the same layer within the eddy current generating module 1. os1 r os1 r os1 r os1 ,like Figure 3 and Figure 4 As shown, AC conductive coils 13 of different diameters are respectively connected to an alternating power supply voltage, such as AC1, AC2, AC3, and AC4. By adjusting these closed circuit voltages, the eddy current density distribution on the surface of the ballast plate 31 can be made more uniform, reducing the stress concentration on the ballast plate 31 and preventing deformation of the ballast plate 31.

[0038] Furthermore, the eddy current generating module 1 also includes multiple partitions 12, each partition 12 is placed horizontally at a distance in the vertical direction, and multiple sets of AC conductive coils 13 are arranged on each partition 12 from the inside to the outside, thereby isolating each layer of AC conductive coils 13 to further expand the adjustment range of eddy current intensity.

[0039] Furthermore, the main function of the magnetic field adjustment module 2 is to excite the electromagnetic force of the ballast plate 31. It includes a winding core 21 and multiple sets of DC conductive coils 22. The winding core 21 is a column structure with a stepped body. The DC conductive coils 22 are wound on each step of the winding core 21 and connected end to end to form a circular closed loop with different diameters. The DC conductive coils 22 form a DC circuit by connecting with a DC power supply and a rheostat. After the circuit is closed, it can emit a magnetic field perpendicular to the ballast plate 31. According to the principle of electromagnetic induction, the eddy currents on the ballast plate 31 interact with the magnetic field to generate an electromagnetic force, which is directed downwards. This causes the ballast plate 31 to apply a load to the test piece 8. The load magnitude is adjusted by rheostats such as R1, R2, and R3 and alternating power supply voltages such as DC1, DC2, and DC3.

[0040] Furthermore, according to Lenz's law, the eddy current generating module 1 generates a magnetic field during the energization process, which is opposite in direction to the magnetic field formed by the eddy currents induced on the ballast plate 31, resulting in a repulsive force between the ballast plate 31 and the eddy current generating module 1. Therefore, an ear plate 9 is installed at the bottom of the housing 11 and fixed to the panel 6 with high-strength bolts, effectively preventing the vibration of some components during platform operation from causing errors in the test results.

[0041] Furthermore, the impact load test platform also includes a tension / compression sensor 10, which is connected to the test piece 8 and is used to provide timely feedback on the mechanical performance data of the test piece 8 during the loading process.

[0042] Furthermore, the housing plate 11 and partition plate 12 of the eddy current generating module 1 and the winding core column 21 of the magnetic field regulating module 2 are all made of insulating materials to avoid eddy current disturbances in the ballast plate caused by uncertain factors such as current direction.

[0043] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An impact load testing platform based on a pulsed strong magnetic field, characterized in that, The impact load test platform includes an impact unit and a power unit. The impact unit is used to fix the test piece (8) and apply a load to it. The power unit is used to provide power for the impact unit to apply the load. It includes an eddy current generating module (1) and a magnetic field regulating module (2) respectively set above and below the impact unit. The eddy current generating module (1) includes an AC conductive coil (13) for connecting to an AC transformer power supply to induce eddy currents in the impact unit. The magnetic field regulating module includes a DC conductive coil (22) for connecting to a DC power supply to form a vertically upward magnetic field, so that the impact unit generates a downward electromagnetic force under the action of eddy currents and magnetic field, thereby providing power for applying the load. The eddy current generating module (1) includes a housing (11), multiple sets of AC conductive coils (13) disposed inside the housing (11), and multiple partitions (12). The bottom of the housing (11) is provided with an ear plate (9) for fixed connection with the impact unit. The AC conductive coils (13) are connected end to end to form a circular closed loop with different diameters and are spaced apart from the inside to the outside. Each partition (12) is placed horizontally at a distance in the vertical direction, and multiple sets of AC conductive coils (13) are spaced apart from the inside to the outside on each partition (12). The magnetic field adjustment module (2) includes a winding core column (21) and multiple sets of DC conductive coils (22). The winding core column (21) is a column structure with a stepped body. The DC conductive coils (22) are wound on each step of the winding core column (21) and connected end to end to form a circular closed loop with different diameters.

2. The impact load test platform based on a pulsed strong magnetic field as described in claim 1, characterized in that, The impact unit includes a panel (6), a test platform (5), a support column (4), and a ballast module (3). The panel (6) and the test platform (5) are respectively fixed at the upper and lower ends of the support column (4). The panel (6) is used to fix the eddy current generating module (1), and the test platform (5) is used to fix the test piece (8). At the same time, the magnetic field adjustment module (2) is set below the test platform (5). The ballast module (3) is slidably connected to the support column (4).

3. The impact load test platform based on a pulsed strong magnetic field as described in claim 2, characterized in that, The ballast module (3) includes a ballast plate (31), a connector (33) and a lifting rod (32). The ballast plate (31) is made of metal material and is used to induce eddy currents and generate electromagnetic force under the action of a magnetic field. The ballast plate (31) is connected to the lifting rod (32) through the connector (33). The lifting rod (32) is slidably connected to the support column (4).

4. The impact load test platform based on a pulsed strong magnetic field as described in claim 3, characterized in that, The support column (4) has a sliding groove (7) inside. The fixed end of the lifting rod (32) is connected to the panel (6), and its movable end is embedded in the sliding groove (7) to slide up and down along the support column (4).

5. The impact load test platform based on a pulsed strong magnetic field as described in claim 4, characterized in that, The test platform (5), connector (33), lifting rod (32) and support column (4) are all made of insulating material.

6. The impact load test platform based on a pulsed strong magnetic field as described in any one of claims 1 to 5, characterized in that, The impact load test platform also includes a tension / compression sensor (10), which is connected to the test piece (8).

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