Vibration test fixture

Abstract

A vibration test tool includes a base plate, a support, a fixed crossbar, a fixed assembly, and a reinforcing member. The base plate is provided with an array of mounting holes connected to a vibration table; the support is fixedly connected to the base plate and extends upward; the fixed crossbar is connected to the support, and the fixed crossbar, the support, and the base plate form an installation space for accommodating a measured member; the fixed assembly includes a first fixed block and a second fixed block, the first fixed block is arranged at one end of the support away from the base plate, and the second fixed block is arranged on the base plate; and the reinforcing member is arranged between the support and the base plate and is connected to the support and the base plate, respectively.

Description

Technical Field

[0001] This application relates to the field of testing fixture technology, and more particularly to a vibration testing fixture for a vibration table. This fixture can be used for clamping and simulating boundary conditions of vehicle thermal management system components, air conditioning cooling system components, and other products requiring mechanical vibration durability verification. Background Technology

[0002] In the development of new energy vehicles and their thermal management systems, components such as condensers, radiators, integrated thermal management modules, cooling fan assemblies, and related pipe supports typically require random vibration, sinusoidal frequency sweep, shock, or combined environmental vibration tests in a mechanical durability laboratory to evaluate the durability and reliability of welds, connections, mounting lugs, vibration damping bushings, and other parts. These vibration tests place high demands on the consistency and repeatability of clamping boundary conditions and the stability of vibration load transfer rates: differences in clamping direction, constraint position, contact method, and force flow path compared to the actual vehicle conditions may lead to localized overload or underload, thus affecting the validity of the test conclusions.

[0003] In the prior art, common clamping methods include: (1) The submitting unit provides the fixture / tooling, and the laboratory directly uses the fixture for testing. This method can approximate the loading state of the submitted sample to a certain extent, but in actual engineering, there are often problems such as unstable fixture sources, incompatible interfaces, insufficient structural strength, or excessive overall mass. When the fixture stiffness is insufficient or the connection is unreliable, it is easy to loosen, resonate, have secondary collisions, or even fall off during the test, which poses a risk to the sample and equipment. (2) Without setting up special tooling, the test piece is directly fixed on the vibration table by pressure plate or temporary support for testing. Although this method saves the time of tooling design and manufacturing, it is difficult to replicate the loading direction of the actual vehicle and the boundary conditions of the test piece. Moreover, the stiffness and damping of the temporary fixing method are uncontrollable, which can easily introduce large uncertainties. Under broadband excitation or high acceleration conditions, the temporary structure is more likely to resonate or loosen, which poses a high safety risk. Summary of the Invention

[0004] To address the aforementioned issues, this application provides a vibration testing fixture that enables the test piece to obtain stable and reproducible installation boundary conditions on a vibration table, while also considering structural strength, stiffness, lightweight design, and versatility.

[0005] The technical solution of this application is as follows: A vibration testing fixture includes a base plate, a support member, a fixed crossbar, a fixing assembly, and a reinforcing member. The base plate has an array of mounting holes for connection to a vibration table, used for interlocking with the vibration table via bolts or other fasteners. The support member is fixedly connected to the base plate and extends upwards. The fixed crossbar is connected to the support member, and the fixed crossbar, the support member, and the base plate form an installation space for accommodating the test piece. The fixing assembly includes a first fixing block and a second fixing block. The first fixing block is disposed at the upper end of the support member and is used for positioning and locking the upper part of the test piece. The second fixing block is disposed on the base plate and is used for positioning the lower part of the test piece. The reinforcing member is disposed between the support member and the base plate and connects the support member and the base plate respectively, used to improve the overall structural stiffness and suppress structural resonance under vibration conditions.

[0006] In some possible implementations, the support includes two spaced-apart support columns, each support column having a connection area and a movable area at its upper end, and a fixed crossbar connecting the two ends to the connection area of ​​the two support columns respectively; a first fixing block is disposed in the movable area and is adjustable along the extension direction of the fixed crossbar, so that the fixture can be adapted to the upper installation position of different test pieces, improving versatility and clamping efficiency.

[0007] In some possible implementations, the support column is provided with weight-reduction windows, which include windows spaced apart along the height direction. These windows are elongated and / or elliptical, thereby achieving weight reduction while maintaining the continuity of the main force path and enabling the support column to form a multi-web beam structure to obtain higher bending and torsional stiffness.

[0008] In some possible implementations, the reinforcement includes a reinforcing plate with a gradually increasing cross-sectional area from top to bottom, forming a gradually changing triangular / trapezoidal force flow channel, which can more smoothly transfer the load on the upper part of the support column to the base plate and reduce stress concentration at the connection; the structural setting of the end face of the reinforcing plate being flush with the end face of the support column is conducive to forming a continuous force boundary and facilitating assembly and positioning.

[0009] In some possible implementations, the base plate is a perforated base plate with a thickness of 20mm to 35mm, and through holes or blind holes are provided to reduce weight. The through holes or blind holes avoid each other with the array of mounting holes, thereby reducing the weight of the tooling while ensuring the strength and stability of the connection with the vibration table.

[0010] In some possible implementations, the base plate, support members, fixed crossbars, and reinforcement members are made of 6061 aluminum alloy, which has good specific strength, machinability, and corrosion resistance, is suitable for CNC machining, and helps to improve vibration transmission stability.

[0011] In some possible implementations, the second fixing block is provided with an insertion hole and is equipped with a replaceable positioning sleeve. By replacing the positioning sleeve with a different inner diameter, different specifications of mounting bushings can be adapted to achieve rapid positioning and repeated clamping of the lower part of the test piece.

[0012] Compared with the prior art, this application has the following advantages: the interlocking connection between the base plate and the vibration table, and the rigid force flow path of the support column-fixed crossbar, make the vibration load transfer rate more stable and the clamping boundary conditions reproducible; the upper and lower positioning and locking structure composed of the first and second fixing blocks can reliably position and fix the test piece in the installation space, reducing the risk of loosening and collision; the lightweighting achieved by the weight-reducing window, the perforated base plate, and the material selection can reduce the load on the vibration table and improve the control stability of the equipment in a wide frequency spectrum; the gradual cross-section structure of the reinforced vertical plate improves the lateral stiffness and disperses stress, which helps to suppress resonance and improve the durability of the tooling, making it suitable for repeated use. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the overall structure of the vibration testing fixture in one embodiment of this application.

[0014] Figure 2 yes Figure 1 The diagram shows a cross-sectional view of the vibration testing fixture along line II-II.

[0015] Figure 3 yes Figure 1 The diagram shows the structural design of the support column for the vibration testing fixture.

[0016] Figure 4 yes Figure 1 The diagram shows the structural schematic of the reinforcing plate of the vibration testing fixture.

[0017] Figure 5 yes Figure 1 The diagram shows the structural diagram of the base plate of the vibration testing fixture.

[0018] Figure 6 yes Figure 1 The diagram shows the structure of the first fixed block of the vibration testing fixture.

[0019] Figure 7 yes Figure 1 The diagram shows the structure of the second fixing block and positioning sleeve of the vibration testing fixture.

[0020] Explanation of main component symbols 100: Vibration testing fixture; 10: Base plate; 11: Mounting hole array; 12: Through hole / blind hole; 20: Support component; 21: Support column; 211: Weight reduction window; 212: Long strip window; 213: Elliptical window; 215: Connection area; 216: Moving area; 30: Fixed crossbar; 40: Fixed component; 41: First fixed block; 411: Positioning boss; 412: Locking hole; 42: Second fixed block; 421: Insertion hole; 422: Positioning sleeve; 50: Reinforcing component; 51: Reinforcing plate; 511: First end; 512: Second end. Detailed Implementation

[0021] The technical solution of this application will be further described below with reference to the accompanying drawings. It should be noted that the described embodiments are only for explaining this application and not for limiting the scope of protection of this application. Other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are all within the scope of protection of this application.

[0022] In the description of this application, the terms "first," "second," etc., are used only to distinguish different components and do not indicate any limitation on quantity or order. The directional terms "upper," "lower," "left," "right," etc., are based on the directions shown in the accompanying drawings and are used only for the convenience of describing this application, and should not be construed as limiting this application.

[0023] like Figures 1 to 7 As shown, this embodiment provides a vibration testing fixture 100. The vibration testing fixture 100 can be installed on a vibration table (not shown) and is used to verify the vibration durability of a test component (not shown). The test component can be an air conditioning cooling system sample in a vehicle thermal management system, or other products that require vibration reliability verification.

[0024] The vibration testing fixture 100 includes a base plate 10, a support member 20, a fixed crossbar 30, a fixing assembly 40, and a reinforcing member 50. The base plate 10 is located at the bottom of the fixture 100, providing an installation reference for connection to the vibration table and serving as the assembly base for all components. The support member 20 is fixedly connected to the base plate 10 and extends upwards, supporting the fixed crossbar 30 and establishing the main transmission path for vibration loads. The fixed crossbar 30 is connected to the upper end of the support member 20, forming an installation space with the fixed crossbar 30, support member 20, and base plate 10, where the test piece is clamped. The fixing assembly 40 is used to position and lock the test piece. The reinforcing member 50 connects the support member 20 and the base plate 10, improving overall stiffness and suppressing structural resonance under vibration conditions.

[0025] See Figure 1 , Figure 2 and Figure 5In some embodiments, the base plate 10 is a plate-like structure, with its upper surface used to mount the support member 20 and the second fixing block 42, and its lower surface in contact with the worktable surface of the vibration table. The base plate 10 is provided with a mounting hole array 11, which is used to cooperate with the threaded hole array or T-slot pressure plate of the vibration table to achieve a reliable interlocking connection between the base plate 10 and the vibration table. To improve connection stability, the mounting hole array 11 can be set as a regular matrix of holes, or it can be customized according to the hole distribution of the vibration table. Some holes in the mounting hole array 11 can be countersunk or countersunk head structures to accommodate bolt heads and avoid interference with components within the installation space.

[0026] In some embodiments, the base plate 10 is a perforated base plate, and the thickness of the base plate 10 is set to 20 mm to 35 mm. In one specific embodiment, the thickness of the base plate 10 is set to 25 mm to obtain higher out-of-plane stiffness and torsional stiffness under common random vibration spectrum and sinusoidal sweep spectrum conditions. The base plate 10 is also provided with through holes or blind holes 12 to reduce its own weight. The through holes or blind holes 12 avoid each other with the mounting hole array 11, that is, the through holes or blind holes 12 are not located in the stress area of ​​the mounting hole array 11, thereby avoiding weakening the strength at the connection with the vibration table. The through holes or blind holes 12 can be arranged in an array along the non-critical stress area of ​​the base plate 10, or the weight-reducing cavity can be formed by pocket milling. Sufficient solid frame is retained in the four peripheral edge areas of the base plate 10 to ensure the integrity of the base plate 10 under vibration conditions.

[0027] To improve clamping consistency, the base plate 10 may also be provided with positioning reference edges, positioning pin holes, or corner markings (not shown) for quick orientation calibration when mounted to the vibration table. For test pieces with directional requirements, this structure can reduce clamping errors and improve test repeatability. In some embodiments, the base plate 10 may be reinforced with stiffeners or locally thickened areas to accommodate connection strength requirements under extreme acceleration spectra.

[0028] See Figures 1 to 3 In some embodiments, the support member 20 includes two spaced-apart support columns 21, which are arranged opposite each other along the extension direction of the fixed crossbar 30 and are respectively fixed to the base plate 10. The two support columns 21, connected to the base plate 10, form a portal / frame-type load-bearing structure, providing support for the fixed crossbar 30. In some embodiments, the number of support columns 21 can be two or more to accommodate test pieces with larger spans or multi-point support.

[0029] Each support column 21 has a connecting area 215 and a movable area 216 at its upper end. The connecting area 215 is located on the side closer to the installation space and is used to connect to the end of the fixed crossbar 30. The movable area 216 is located outside the connecting area 215 and is used to install the first fixing block 41 and provide adjustment stroke. By separating the fixed crossbar 30 and the first fixing block 41 in the connecting area 215 and the movable area 216, the fixed crossbar 30 can bear the main span support function, while the first fixing block 41 bears the positioning and locking function of the upper part of the test piece. The two are relatively independent, which is beneficial for clamping adjustment and force path stability.

[0030] The support column 21 is provided with weight-reduction windows 211. The weight-reduction windows 211 are CNC machined and include elongated windows 212 and / or elliptical windows 213 spaced apart along the height direction. The elongated windows 212 are arranged along the height direction of the support column 21 to reduce material usage without significantly reducing the moment of inertia of the cross section. The elliptical windows 213 are used to smooth stress transitions and reduce stress concentration at the opening edges. The weight-reduction windows 211 enable the support column 21 to form a multi-web beam structure, improving specific stiffness and reducing the overall mass of the tooling. In some embodiments, the shape, number, and arrangement of the weight-reduction windows 211 can be adjusted according to topology optimization results to balance mass and stiffness.

[0031] The support column 21 and the base plate 10 can be detachably assembled by bolt connection, or a bolt connection combined with a locating pin can achieve high repeatability positioning accuracy. The lower end of the support column 21 can be provided with a positioning step or positioning surface (not shown in the figure) to cooperate with the corresponding positioning surface on the base plate 10, further improving assembly consistency.

[0032] See Figure 1 and Figure 2 In some embodiments, the fixed crossbar 30 spans between two support columns 21, with its two ends connected to the connection area 215 of the two support columns 21, thereby forming a stable upper connection between the support columns 21. The fixed crossbar 30 and the support columns 21 together constitute a frame structure, giving the upper boundary of the installation space high bending and torsional resistance.

[0033] The fixed crossbar 30 can be a rectangular cross-section beam, an I-beam, a channel steel beam, or a box-shaped beam structure formed by bending / welding sheet metal. In some embodiments, the fixed crossbar 30 is a long strip beam structure with several connecting holes on its upper surface or side to connect with the connecting area 215 of the supporting column 21. The cross-sectional shape and wall thickness of the fixed crossbar 30 can be designed according to the vibration spectrum requirements, the mass of the test piece, and the size of the installation space to ensure that excessive deflection affecting the test does not occur within the target frequency band.

[0034] The fixed crossbar 30 not only serves to connect the two support columns 21, but also acts as an installation reference for the upper constraint, ensuring that the adjustment reference of the first fixed block 41 is consistent with the clamping reference of the workpiece being measured.

[0035] See Figure 1 , Figure 2 , Figure 6 and Figure 7 In some embodiments, the fixing component 40 includes a first fixing block 41 and a second fixing block 42. The first fixing block 41 is disposed in the movable area 216 at the upper end of the support column 21, and the second fixing block 42 is disposed on the base plate 10. The first fixing block 41 and the second fixing block 42 form a positioning and locking structure that fits in a vertically cooperating manner, so that the test piece obtains a stable clamping boundary within the installation space.

[0036] See Figure 6 The first fixing block 41 is a block-shaped structure, and its bottom surface is fitted into the movable area 216 of the supporting column 21. The first fixing block 41 includes a positioning boss 411 and a locking hole 412. The positioning boss 411 is located on the side of the first fixing block 41 facing the installation space and protrudes, and is used to cooperate with the upper positioning surface or mounting ear of the test piece to achieve rapid positioning. The locking hole 412 is a through hole or a threaded hole, used for a locking bolt to pass through and press the test piece in the direction of the installation space, thereby limiting the relative displacement of the test piece in the vertical direction.

[0037] Combination Figure 3 As described in claim 3, the first fixing block 41 is movably disposed in the active area 216 along the extending direction of the fixing crossbar 30. In one specific implementation, a linear guide surface or a groove (not shown) is provided on the active area 216, and the first fixing block 41 cooperates with the guide surface through a slider structure. Alternatively, an elongated hole is provided in the active area 216, and the first fixing block 41 cooperates with the elongated hole through a fastening bolt, allowing its position to be adjusted along the extending direction of the fixing crossbar 30 after the fastening bolt is loosened. Through the above adjustment structure, the upper mounting position of different test pieces can be adapted, reducing the cost of repeatedly manufacturing tooling for different models of test pieces. In some embodiments, the adjustment of the first fixing block 41 can be achieved by using a groove, guide rail, elongated hole, or rack positioning structure.

[0038] See Figure 7In some embodiments, the second fixing block 42 is a block-shaped base, which is fixedly connected to the base plate 10 by bolts. The second fixing block 42 is provided with an insertion hole 421, in which a replaceable positioning sleeve 422 is disposed. The positioning sleeve 422 can be a sleeve structure with a flange, the outer side of which mates with the insertion hole 421, and the inner hole is used to mate with the lower mounting bushing or positioning shaft of the test piece. When it is necessary to adapt to different specifications of bushing outer diameter, the hole diameter can be switched by disassembling and assembling the positioning sleeve 422 without replacing the second fixing block 42 body, thereby improving the versatility and maintenance efficiency of the tooling. In some embodiments, the second fixing block 42 can be arranged in two, four or more pieces, and the positioning sleeve 422 can adopt a quick-change snap-fit ​​structure to improve replacement efficiency.

[0039] See Figure 1 , Figure 2 and Figure 4 In some embodiments, the reinforcement 50 includes a reinforcing plate 51. The reinforcing plate 51 is connected between the support column 21 and the base plate 10 to improve the lateral stiffness of the vibration testing fixture 100 and to more smoothly transfer the load on the support column 21 to the base plate 10, thereby reducing stress concentration at the connection.

[0040] The reinforcing plate 51 includes a first end 511 and a second end 512. The first end 511 is connected to the end of the supporting column 21 away from the base plate 10, and the second end 512 is connected to the base plate 10 and to the end of the supporting column 21 near the base plate 10. From the first end 511 to the second end 512, the cross-sectional area of ​​the reinforcing plate 51 increases. In some embodiments, the reinforcing plate 51 unfolds in a triangular or trapezoidal shape in the vertical direction, such that its lower end is wider than its upper end, thereby providing a larger bending section and stronger torsional support in the area near the base plate 10.

[0041] Combination Figure 4 According to the structure of claim 6, in the assembled state, the end face of the first end 511 facing away from the base plate 10 is flush with the end face of the supporting column 21 facing away from the base plate 10, and the end face of the second end 512 facing away from the first end 511 is flush with the end face of the supporting column 21 facing towards the base plate 10. This flush structure makes the reinforcing plate 51 and the supporting column 21 form a continuous boundary at the upper and lower ends, which is beneficial for assembly positioning and avoids local stress concentration caused by misalignment of the end faces.

[0042] The connection between the reinforced upright plate 51 and the supporting column 21 and the base plate 10 can be achieved by bolting, welding, or a combination of both. When welding is used, stress relief treatment can be performed after welding to reduce the impact of residual stress on vibration response.

[0043] In this embodiment, the base plate 10, support column 21, fixed crossbar 30, and reinforcing plate 51 are made of 6061 aluminum alloy. 6061 aluminum alloy has good machinability and specific strength, making it easy to CNC machine into structures such as mounting hole array 11, through holes or blind holes 12, and weight-reducing windows 211. While meeting the requirements for connection strength and rigidity, the overall mass can be reduced by setting weight-reducing holes / windows on the base plate 10 and support column 21, thereby reducing the load on the vibration table and increasing the equipment control margin.

[0044] In an exemplary design verification, a finite element model of the vibration testing fixture 100 can be established and modal analysis and vibration response analysis can be performed to evaluate the natural frequency distribution, displacement response, and stress level of the vibration testing fixture 100 under the target excitation spectrum. For example, under one analysis condition, the maximum displacement response of the vibration testing fixture 100 can be controlled within the range of 0.23 mm, and the maximum equivalent stress at key locations is approximately 13.1 MPa, both of which meet the strength and reusability requirements of 6061 aluminum alloy with a yield strength of 259 MPa. The above values ​​are exemplary analysis results, and their specific values ​​may vary depending on the mass of the tested component, the connection method, and the vibration spectrum parameters.

[0045] When vibration testing is required, the base plate 10 of the vibration testing fixture 100 can be connected to the vibration table through the mounting hole array 11 and tightened to the specified torque. The test piece is placed in the installation space, with its lower mounting bushing engaging with the positioning sleeve 422 of the second fixing block 42 for positioning. The position of the first fixing block 41 in the movable area 216 is then adjusted so that the positioning boss 411 is in contact with the upper positioning surface of the test piece. The locking bolt passes through the locking hole 412 and presses the test piece to complete the locking. After the test is completed, the locking bolts can be loosened in reverse order and the test piece can be removed. With the above structure, this application can achieve rapid clamping and repeated clamping while ensuring connection stability, which is suitable for the batch vibration testing needs of mechanical durability laboratories.

[0046] In summary, the vibration testing fixture 100 provided in this application achieves real-vehicle installation simulation of the air conditioning cooling system in the mechanical durability laboratory through structural design and material optimization. Furthermore, the stability of vibration transmission rate and structural reliability are ensured through measures such as the thickness design of the base plate 10, the reinforcing rib structure, the double reinforcement connection, and lightweight processing.

[0047] This application has the following beneficial effects: the interlocking connection between the base plate 10 and the vibration table, and the rigid force flow path of the support column 21-fixed crossbar 30, make the vibration load transmission rate more stable and the clamping boundary conditions reproducible; the upper and lower positioning and locking structure formed by the first fixing block 41 and the second fixing block 42 can realize the reliable positioning and fixing of the test piece in the installation space, reducing the risk of loosening and collision; the weight reduction window 211, the perforated base plate 10 and the material selection achieve lightweighting, which can reduce the load on the vibration table and improve the control stability of the equipment in a wide frequency spectrum; the gradual cross-section structure of the reinforced vertical plate 51 improves the lateral stiffness and disperses the stress, which helps to suppress resonance and improve the durability of the vibration testing fixture 100, making it suitable for repeated use.

[0048] Those skilled in the art may also make other changes based on this application, such as changing the arrangement of the hole array 11, adjusting the number of side support components, selecting different connection methods, or setting more degrees of freedom for temperature compensation, etc., and these changes made based on this application should be included within the protection scope of this application.

Claims

1. A vibration testing fixture, characterized in that, include: The base plate is provided with an array of mounting holes for connection with the vibration table; A support member, which is fixedly connected to the base plate and extends upward; A fixed crossbar is connected to the support member, and the fixed crossbar, the support member, and the base plate form an installation space for accommodating the test piece. A fixing component, the fixing component including a first fixing block and a second fixing block, the first fixing block being disposed at the end of the support member opposite to the base plate, and the second fixing block being disposed on the base plate; A reinforcing member is provided between the support member and the base plate, and connects the support member and the base plate respectively.

2. The vibration testing fixture as described in claim 1, characterized in that, The support includes two support columns spaced apart. Each support column has a connecting area and a movable area other than the connecting area at the end away from the base plate. The connecting area is closer to the installation space than the movable area. The two ends of the fixed crossbar are respectively connected to the connecting areas of the two support columns.

3. The vibration testing fixture as described in claim 2, characterized in that, Each of the aforementioned active areas is provided with a first fixing block, which is movably disposed in the active area along the extension direction of the fixing crossbar.

4. The vibration testing fixture as described in claim 2, characterized in that, The supporting column is provided with a weight reduction window, which includes windows spaced apart along the height direction, and the window is at least one of a long strip window and an elliptical window.

5. The vibration testing fixture as described in claim 1, characterized in that, The reinforcing member includes a reinforcing plate, which has a first end and a second end connected to the first end. The first end is connected to the end of the support member away from the base plate, and the second end is connected to the base plate and the end of the support member close to the base plate. The cross-sectional area of ​​the reinforcing plate increases from the first end to the second end.

6. The vibration testing fixture as described in claim 5, characterized in that, The end face of the first end facing away from the base plate is flush with the end face of the support member facing away from the base plate, and the end face of the second end facing away from the first end is flush with the end face of the support member facing the base plate.

7. The vibration testing fixture as described in claim 1, characterized in that, The base plate is a perforated base plate with a thickness of 20mm to 35mm. The base plate is provided with through holes or blind holes, which avoid each other from the mounting hole array.

8. The vibration testing fixture as described in claim 1, characterized in that, The base plate, the support member, the fixed crossbar, and the reinforcing member are made of 6061 aluminum alloy.

9. The vibration testing fixture as described in claim 1, characterized in that, The first fixing block includes a positioning boss and a locking hole. The positioning boss is located on the side of the first fixing block facing the installation space and protrudes from the first fixing block. The locking hole is for a locking bolt to pass through to press the fixed part towards the installation space.

10. The vibration testing fixture as described in claim 1, characterized in that, The second fixing block is provided with an insertion hole, and a replaceable positioning sleeve is provided in the insertion hole.

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