Impact resistance testing device for skylight bracket

Abstract

The invention discloses an impact resistance testing device for a skylight support, relates to the technical field of automobile testing, aims to solve the technical problem that a current testing method for the skylight support is too single, and comprises a load platform, a tool clamp, a hydraulic mechanism, a variable pitch mechanism and a multi-mode impact mechanism. The multi-mode impact mechanism comprises a dynamic box, a gradient module, a rigid rod set, a load applying assembly and a rigidity execution unit, and the gradient module is configured to selectively drive the rigid rod set to act so that the load applying assembly can achieve dynamic impact which is gradually expanded from the center to the periphery, or the gradient module can be selectively locked at at least two different preset radius positions so that the rigidity execution unit can execute the rigidity of the rigid rod set. And a magnetorheological fluid damping cavity and a rigidity execution unit capable of generating a magnetic field are arranged in the load applying assembly, and the load applying assembly is used for dynamically adjusting the impact rigidity. According to the invention, various actual working conditions such as hail impact diffusion and multi-point constant impact can be simulated, and the impact resistance of the skylight bracket can be comprehensively evaluated.

Description

Technical Field

[0001] This invention relates to the field of automotive testing technology, and more specifically, to a sunroof bracket impact resistance testing device. Background Technology

[0002] With the increasing popularity of electric vehicles, roof designs equipped with panoramic sunroofs or sunroofs are becoming more common. While these designs significantly improve the interior's visibility and lighting, and also address weight reduction requirements, their safety performance has become a major concern. The safety of a sunroof system depends not only on the strength of the glass itself, but also on the structural strength and impact resistance of the sunroof brackets that support and secure the glass. As a critical load-bearing and force-transmitting component, insufficient impact resistance of the brackets could lead to complete sunroof failure in extreme situations, endangering occupant safety. Therefore, conducting scientific and rigorous impact tests on sunroof brackets is crucial for ensuring the passive safety of the entire vehicle.

[0003] Currently, in the field of electric vehicle-related facility manufacturing, the mechanical performance testing of sunroof brackets in the industry mostly focuses on traditional static compressive strength testing or material yield strength testing. While these methods can assess the load-bearing limit of the bracket under slow loading, they cannot effectively simulate the complex and transient impact loads that vehicles may encounter in real-world usage scenarios, such as impacts from flying stones, hail, or accidental strikes from falling objects. Existing impact testing devices are often too simplistic, with a single impact method and fixed loading points, making it difficult to simulate the dynamic diffusion of impact force on the bracket structure, and also unable to systematically evaluate the bracket's response under different regions and impact energies. This lack of testing capability leads to blind spots in the evaluation of the bracket's true performance under actual working conditions, making it difficult to fully verify its reliability.

[0004] Therefore, there is an urgent need to develop a dedicated testing device capable of more realistically simulating complex impact scenarios and providing multi-mode loading to fill the gaps in existing technologies and achieve a more scientific and comprehensive evaluation of the impact resistance performance of sunroof brackets, thereby promoting the improvement of the safety design level of electric vehicle sunroof systems. In view of this, we propose a sunroof bracket impact resistance testing device. Summary of the Invention

[0005] The purpose of this invention is to provide a sunroof bracket impact resistance testing device to solve the technical problem that the current testing methods for sunroof brackets are too simplistic.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a sunroof bracket impact resistance testing device, comprising a load platform, tooling fixtures, a hydraulic mechanism, a pitch-changing mechanism, and a multi-mode impact mechanism; The tooling fixture is set on the load platform and is used to fix the sunroof bracket to be tested. The hydraulic mechanism is located at the top of the load platform, and the variable pitch mechanism is suspended at its output end. The multi-mode impact mechanism is located at the output end of the variable pitch mechanism and includes a dynamic box, a gradient module, a rigid bar group, a loading component, and a stiffness execution unit. The dynamic box is fixed at the output end of the pitch mechanism; The gradient module is disposed inside the dynamic box; The rigid bar assembly is movably disposed within the dynamic box, with one end connected to the gradient module drive and the other end extending out of the dynamic box and fixedly connected to the loading component. The stiffness actuation unit is built into the loading component; The gradient module is configured to selectively drive the rigid bar assembly to achieve a dynamic impact that expands gradually from the center to the periphery; or, the gradient module can be selectively locked at at least two different preset radius positions to achieve a constant impact corresponding to the selected radius.

[0007] Preferably, the dynamic box includes a box body, a dynamic chamber, a partition, and a movable chamber. The box body is fixedly connected to the output end of the variable pitch mechanism. The dynamic chamber is opened at the top inside the box body. The partition is fixedly disposed at the bottom inside the box body. The movable chamber is disposed between the bottom of the box body and the partition. The gradient module is disposed in the dynamic chamber. The rigid rod group is movably inserted into the partition, the movable chamber, and the bottom of the box body.

[0008] Preferably, the partition and the bottom of the box are provided with movable holes at equal intervals in a linear pattern, and the rigid rod assembly is movably inserted into the movable holes.

[0009] Preferably, the gradient module includes a power source, a power rod, a rack, a ring sleeve, and a contact ring. The power source is fixedly disposed on the outer wall of the dynamic box. One end of the power rod is fixedly connected to the output end of the power source, and the other end of the power rod is rotatably inserted into the interior of the dynamic box. The rack is fixedly connected to the power rod. A plurality of ring sleeves are sequentially deflected and sleeved on the rack, and the contact ring is fixedly sleeved on the ring sleeve.

[0010] Preferably, the inner wall of the ring sleeve is provided with a protrusion, and the protrusion has a toothed hole adapted to the toothed rod. Several ring sleeves are sequentially deflected onto the toothed rod through the toothed hole on the protrusion.

[0011] Preferably, the rigid rod assembly includes movable rigid rods and contact ball heads. A plurality of movable rigid rods are movably inserted into the bottom end of the dynamic box. The bottom end of the movable rigid rod is fixedly connected to the load-applying component. The contact ball head is rotatably disposed on the movable rigid rod. The end of the contact ball head away from the movable rigid rod is movably connected to the gradient module.

[0012] Preferably, the loading assembly includes a plurality of loading blocks that are movably nested together and whose size increases or decreases, and the plurality of loading blocks are connected to the bottom end of the rigid bar assembly.

[0013] Preferably, a damping cavity is provided at the top of the loading block, a buffer ring is slidably provided on the damping cavity, the end of the rigid rod assembly away from the dynamic box is fixedly connected to the buffer ring, and magnetorheological fluid is provided in the damping cavity.

[0014] Preferably, the stiffness actuation unit includes a bottom ring plate, a magnetic control cavity, and a ring wave coil. The bottom ring plate is fixedly disposed at the bottom end of the loading block, the magnetic control cavity is opened between the bottom ring plate and the bottom end of the inner wall of the loading block, and the ring wave coil is disposed inside the magnetic control cavity.

[0015] Preferably, the ring wave coil is arranged in a ring-shaped wave pattern inside the magnetron cavity, and one end of the ring wave coil passes through the outer wall of the loading block and is electrically connected to the outside.

[0016] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention integrates a load platform, tooling fixtures, hydraulic loading, variable-pitch positioning, and a core multi-mode impact mechanism to form an automated, multi-functional testing platform specifically for sunroof supports. This device can not only perform traditional quasi-static or single-point impact tests, but more importantly, it can conveniently switch and execute multiple complex dynamic impact test modes in a single setup using the same equipment. This integrated design avoids the cumbersome process of frequently changing test equipment or tooling to simulate different working conditions, greatly improving testing efficiency and significantly expanding the evaluation coverage of the impact resistance performance of sunroof supports using a single device.

[0017] 2. The multi-mode impact mechanism of this invention, through the synergistic effect of unique gradient modules, rigid bar groups, and nested loading components, can achieve dynamic impacts that expand progressively from the center outwards. This mode accurately simulates the real physical process of impact energy propagating and diffusing outwards from the impact point on the support structure after an object such as hail or flying stone strikes a skylight. This testing mode can effectively evaluate the overall deformation coordination, stress distribution, and potential fatigue weaknesses of the support structure under dynamic expanding loads, solving the technical problem that traditional single-point, instantaneous impact tests cannot reflect the shock wave propagation effect.

[0018] 3. The gradient module of this invention can be locked at different preset radius positions, thereby enabling the specific annular loading block group to operate synchronously, achieving a constant impact corresponding to the selected radius. This mode allows testers to programmatically select different impact areas, such as the central area, edge area, or specific reinforcing rib positions, for multi-point synchronous impact testing based on the design characteristics and risk assessment of the sunroof bracket. This enables a systematic evaluation of the bracket's local stiffness, bearing capacity, and failure mode under different specific stress distributions, providing a highly targeted and data-comparable testing method for the optimized design of the bracket.

[0019] 4. This invention integrates a stiffness actuation unit based on magnetorheological fluid technology within the loading assembly. By controlling the current in the ring coil, the rheological state of the magnetorheological fluid within the damping cavity can be changed in real time and rapidly, thereby dynamically adjusting the impact stiffness and load waveform during a single impact. This innovation allows the same device to simulate the impact characteristics of objects with varying hardness, from rigid to flexible, as well as the process of impact energy absorption. This greatly enhances the realism of the test scenario simulation, making the evaluation of the sunroof bracket's impact resistance performance more closely resemble the complex and ever-changing actual usage environment. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of one side of the overall structure of the present invention.

[0021] Figure 2 This is a schematic diagram of the other side of the overall structure of the present invention.

[0022] Figure 3 This is a schematic diagram of the hydraulic mechanism, pitch-changing mechanism, and multi-mode impact mechanism of the present invention.

[0023] Figure 4 This is a schematic diagram of the bottom structure of the variable pitch mechanism and multi-mode impact mechanism of the present invention.

[0024] Figure 5 This is a schematic diagram of the top structure of the variable pitch mechanism and multi-mode impact mechanism of the present invention.

[0025] Figure 6 This is a schematic diagram of the output end of the variable pitch mechanism and the dynamic box structure of the present invention.

[0026] Figure 7 This is a cross-sectional view of the dynamic box and an assembly diagram of the gradient module, rigid bar group and loading components of the present invention.

[0027] Figure 8 This is a schematic diagram of the gradient module and rigid bar assembly structure of the present invention.

[0028] Figure 9 For the present invention Figure 8 Enlarged view of the structure at point A in the image.

[0029] Figure 10 This is a schematic diagram of the ring structure of the present invention.

[0030] Figure 11 This is a schematic diagram of the cross-sectional split of the loading block and the stiffness execution unit structure of the present invention.

[0031] Figure 12 This is a schematic diagram of the dynamic impact sequence of the loading components of the multi-mode impact mechanism of the present invention.

[0032] Explanation of the labels in the diagram: 1. Loading platform; 2. Tooling fixtures; 3. Hydraulic mechanism; 4. Pitch-changing mechanism; 5. Multi-mode impact mechanism; 501. Dynamic box; 502. Gradient module; 503. Rigid bar assembly; 504. Loading component; 505. Stiffness actuation unit; 5011, Enclosure; 5012, Dynamic Chamber; 5013, Partition; 5014, Movable Chamber; 5015, Movable Hole; 5021, Power source; 5022, Power rod; 5023, Gear rack; 5024, Ring sleeve; 5025, Contact ring; 5026, Protrusion; 5027, Tooth hole; 5031, movable rigid rod; 5032, contact ball head; 5041, Loading block; 5042, Damping cavity; 5043, Buffer ring; 5051, bottom ring plate; 5052, magnetic control cavity; 5053, ring coil. Detailed Implementation

[0033] like Figures 1 to 12 As shown, the present invention relates to a sunroof bracket impact resistance testing device, which includes a load platform 1, a tooling fixture 2, a hydraulic mechanism 3, a pitch mechanism 4, and a multi-mode impact mechanism 5. The tooling fixture 2 is set on the load platform 1 to fix the sunroof bracket to be tested; The hydraulic mechanism 3 is located at the top of the load platform 1, and a pitch-changing mechanism 4 is suspended at its output end; The multi-mode impact mechanism 5 is located at the output end of the variable pitch mechanism 4 and includes a dynamic box 501, a gradient module 502, a rigid bar group 503, a loading component 504, and a stiffness execution unit 505. Among them, the dynamic box 501 is fixed at the output end of the pitch mechanism 4; Gradient module 502 is located inside dynamic box 501; The rigid bar assembly 503 is movably installed inside the dynamic box 501. One end of it is driven and connected to the gradient module 502, and the other end extends out of the dynamic box 501 and is fixedly connected to the loading component 504. The stiffness actuation unit 505 is built into the load application component 504; The gradient module 502 is configured to selectively drive the rigid bar assembly 503 to achieve a dynamic impact that expands from the center to the periphery of the loading assembly 504; or, the gradient module 502 can be selectively locked at at least two different preset radius positions to achieve a constant impact corresponding to the selected radius of the loading assembly 504.

[0034] In use, the sunroof bracket under test is securely fixed to the load platform 1 using the tooling fixture 2. The height of the entire impact system is adjusted by the hydraulic mechanism 3, and horizontal alignment is achieved using the pitch mechanism 4, ensuring that the multi-mode impact mechanism 5 is precisely aligned with the test area. During the core test, the gradient module 502 has two operating modes: In dynamic impact mode, the gradient module 502 selectively drives the rigid rod group 503 to move, causing the loading component 504 to generate a continuous dynamic load that expands gradually from the impact center outwards, simulating the real physical process of shock wave diffusion after an impact from an object such as hail; In static multi-point impact mode, the gradient module 502 can be selectively locked at a specific preset radius position. At this time, the loading component 504 applies a constant impact force corresponding to the selected radius and synchronized at multiple points to the sunroof bracket, in order to evaluate the structural response of the bracket under a specific force distribution. By integrating the above two core impact modes, this device effectively overcomes the limitations of traditional single testing methods and can more realistically and comprehensively simulate and evaluate the impact resistance performance of the sunroof bracket under actual complex working conditions.

[0035] In an embodiment of the present invention, the dynamic box 501 includes a box body 5011, a dynamic chamber 5012, a partition 5013, and a movable chamber 5014. The box body 5011 is fixedly connected to the output end of the variable pitch mechanism 4. The dynamic chamber 5012 is opened at the top inside the box body 5011. The partition 5013 is fixedly disposed at the bottom inside the box body 5011. The movable chamber 5014 is disposed between the bottom of the box body 5011 and the partition 5013. The gradient module 502 is disposed in the dynamic chamber 5012. The rigid rod group 503 is movably inserted into the partition 5013, the movable chamber 5014, and the bottom of the box body 5011.

[0036] In this embodiment, the dynamic chamber 501 serves as the integrated carrier and action space for the multi-mode impact mechanism 5. Its internal structure functionally partitions the core drive and execution components: the top dynamic chamber 5012 houses and protects the drive portion of the gradient module 502; the bottom movable chamber 5014 provides a vertically movable guide space for the rigid rod assembly 503. During operation, the chamber 5011 accurately transmits the impact load to the support through the positioning of the pitch mechanism 4; the driving action generated by the gradient module 502 in the dynamic chamber 5012 is transmitted to the outside via the rigid rod assembly 503, through the partition 5013, and the bottom of the chamber 5011. This partitioning design not only ensures the accuracy and reliability of the coordinated operation of each component, but the partition 5013 also isolates the drive space from the execution space, preventing motion interference and ensuring a clear and stable impact force transmission path, providing a solid mechanical foundation for the subsequent realization of complex dynamic and static impact modes.

[0037] In an embodiment of the present invention, the bottom ends of the partition 5013 and the box 5011 are provided with movable holes 5015 at equal intervals in a linear pattern, and the rigid rod group 503 is movably inserted into the movable holes 5015.

[0038] In this embodiment, the movable holes 5015, which are linearly spaced at equal intervals at the bottom of the partition plate 5013 and the housing 5011, constitute a key guiding and constraining mechanism for the rigid rod assembly 503. This layout ensures that the multiple movable rigid rods are arranged in a linear array in space with equal spacing. During operation, each rod of the rigid rod assembly 503 slides in the corresponding movable hole 5015. These holes precisely define its movement trajectory, ensuring that all rods maintain parallel and stable vertical movement during impact, preventing lateral deviation or mutual interference.

[0039] In another embodiment of the present invention, the gradient module 502 includes a power source 5021, a power rod 5022, a rack 5023, a ring sleeve 5024, and a contact ring 5025. The power source 5021 is fixedly disposed on the outer wall of the dynamic box 501. One end of the power rod 5022 is fixedly connected to the output end of the power source 5021, and the other end of the power rod 5022 is rotatably inserted into the interior of the dynamic box 501. The rack 5023 is fixedly connected to the power rod 5022. Several ring sleeves 5024 are sequentially deflected and sleeved on the rack 5023. The contact ring 5025 is fixedly sleeved on the ring sleeves 5024.

[0040] In this invention, the power source 5021, such as a servo motor, serves as the driving core. Its output drives the rack 5023 fixed to it to rotate via the power rod 5022. Crucially, the several rings 5024 are not simply fixed to the rack 5023, but are sequentially deflected. This design ensures that each ring 5024 and its fixed contact ring 5025 have different phase angles in the circumferential direction of the rack 5023. When the rack 5023 rotates, these contact rings 5025 with different phases will reach their highest point or driving position at different times in a preset order, thus sequentially contacting and pushing the moving rods in the corresponding rigid rod assembly 503. This achieves the core function of accurately simulating dynamic impacts that gradually expand from the center outwards, starting from a central point and triggering the impact action sequentially in the radial direction according to a set sequence. It provides a concrete, reliable, and controllable mechanical execution scheme, realizing the orderly transmission of impact force in space and time.

[0041] In another embodiment of the present invention, the inner wall of the ring 5024 is provided with a protrusion 5026, and the protrusion 5026 is provided with a toothed hole 5027 adapted to the toothed rod 5023. Several rings 5024 are sequentially deflected onto the toothed rod 5023 through the toothed hole 5027 on the protrusion 5026.

[0042] More specifically, the gear ratio of the toothed bar 5023 of the present invention is the same as the gear ratio of the toothed hole 5027 opened on the protrusion 5026, and the toothed hole 5027 of each adjacent ring 5024 is deflected by two gear ratios and is sequentially sleeved on the toothed bar 5023.

[0043] Therefore, the continuous rotational motion of the rack 5023 is converted into intermittent lifting motion of each contact ring 5025 sequentially reaching the drive apex in a time sequence. This structure achieves single-input, sequential output control of multiple impact actuators, and the mechanical structure is simple and reliable. Its advantage lies in the fact that only one power source 5021 and one rack 5023 are needed to accurately generate impact trigger signals with gradient distributions in both space and time.

[0044] The gradient module 502 also includes a locking unit. This locking unit comprises an electromagnetic brake or pneumatic brake fixed to the dynamic housing 501, with its brake disc coaxially fixed to the power rod 5022 or rack 5023. When a constant impact mode is required, the control system first drives the power source 5021 to rotate the rack 5023 to a preset angular position, corresponding to the required impact radius. Then, the electromagnetic brake is activated to lock the rotating shaft, thus achieving locking. At least two different preset radius positions are achieved by programming the position of the power source 5021, such as a servo motor, to control the rack 5023 to stop at corresponding different rotation angles.

[0045] In an embodiment of the present invention, the rigid rod assembly 503 includes a movable rigid rod 5031 and a contact ball head 5032. A plurality of movable rigid rods 5031 are movably inserted into the bottom end of the dynamic box 501. The bottom end of the movable rigid rod 5031 is fixedly connected to the load application component 504. The contact ball head 5032 is rotatably disposed on the movable rigid rod 5031. The end of the contact ball head 5032 away from the movable rigid rod 5031 is movably connected to the gradient module 502.

[0046] In this embodiment of the invention, the rigid rod assembly 503 serves as a key force transmission component that converts the driving motion of the gradient module 502 into the impact motion of the load application component 504. The movable rigid rod 5031 undertakes the main force transmission and guiding functions, with its bottom end fixed to the load application component 504, transmitting the driving force from the upper part downwards without loss. Its innovation lies in the rotatable contact ball head 5032 provided at the top of the movable rigid rod 5031. This design allows the contact ball head 5032 to rotate freely when the rotating profile surface of the contact ring 5025 of the gradient module 502 pushes it, thereby converting sliding friction into rolling friction and greatly reducing motion resistance and wear. Simultaneously, the spherical contact method can adapt to changes in the angle of the contact ring 5025 surface, ensuring that the driving force is always effectively transmitted along the axial direction of the movable rigid rod 5031, avoiding lateral force components caused by angular deviations, and guaranteeing the vertical accuracy and force transmission efficiency of the impact motion.

[0047] In an embodiment of the present invention, the loading component 504 includes a plurality of loading blocks 5041 that are movably nested together and whose size increases or decreases, and the plurality of loading blocks 5041 are connected to the bottom end of the rigid rod assembly 503.

[0048] In this embodiment, the loading assembly 504 reveals a specific end-effector structure simulating an impact effect that gradually expands from the center outwards. This assembly consists of several annular loading blocks 5041 with gradually varying diameters, and these loading blocks are arranged in a mutually movably nested manner to form a coaxial nested impact head array. Each loading block 5041 is fixedly connected to the bottom end of two corresponding movable rigid rods 5031.

[0049] When the gradient module 502 drives the rigid rod assembly 503 to operate in a specific sequence, the load-applying blocks 5041 of different diameters connected to it will move downwards sequentially according to that sequence. For example, Figure 12 As shown, when the smallest loading block 5041 at the center is driven sequentially, and the larger loading blocks 5041 at the periphery are driven in turn, the impact load achieves a dynamic effect on the test surface where the impact area expands outward in concentric circles from the center point. (See [reference]). Figure 12The impact window is formed by the load block 5041 marked with gray number "1", followed by the load block 5041 marked with gray number "2", then the load block 5041 marked with gray number "3", then the load block 5041 marked with gray number "4", and finally the load block 5041 marked with gray number "5".

[0050] This mechanically nested structure directly and reliably maps the driving sequence to the physical expansion of the impact region, perfectly simulating the real physical process of shock wave propagation on the structure. Its beneficial effect is that it provides an intuitive, controllable, and repeatable physical means to accurately reproduce the spatial propagation pattern of dynamic impact loads, significantly enhancing the realism and scientific rigor of the test.

[0051] In another embodiment of the present invention, a damping cavity 5042 is provided at the top of the loading block 5041, a buffer ring 5043 is slidably provided on the damping cavity 5042, and the end of the rigid rod assembly 503 away from the dynamic box 501 is fixedly connected to the buffer ring 5043. The damping cavity 5042 is provided with magnetorheological fluid.

[0052] In another embodiment of the present invention, the stiffness execution unit 505 includes a bottom ring plate 5051, a magnetic control cavity 5052 and a ring wave coil 5053. The bottom ring plate 5051 is fixedly disposed at the bottom end of the loading block 5041, the magnetic control cavity 5052 is opened between the bottom ring plate 5051 and the bottom end of the inner wall of the loading block 5041, and the ring wave coil 5053 is disposed in the magnetic control cavity 5052.

[0053] In this invention, when the rigid rod assembly 503 drives the buffer ring to move downwards, the buffer ring compresses the magnetorheological fluid in the damping cavity 5042, forcing it to flow. Magnetorheological fluid is a smart fluid whose properties can change significantly under the control of an external magnetic field. By supplying a controllable current to the ring coil 5053, a high-intensity, spatially controlled magnetic field is generated within and around the magnetically controlled cavity 5052, particularly in the damping cavity 5042 region above, based on the principle of electromagnetic induction. In the absence of a magnetic field, it behaves as a low-viscosity Newtonian fluid, allowing the buffer ring to move rapidly, simulating a rigid impact. When a magnetic field is applied, its yield strength increases dramatically within milliseconds, exhibiting a high-damping state similar to a solid, thus generating significant resistance to the movement of the buffer ring and playing a significant role in buffering and energy dissipation, simulating flexible or attenuated impacts. This allows the device of the present invention to not only simulate the physical process of impact propagation on a structure but also to simulate impacts from falling objects of varying hardness, greatly expanding the coverage of test scenarios and the realism of the simulation.

[0054] In an embodiment of the present invention, the ring coil 5053 is arranged in a ring-shaped wave pattern inside the magnetron cavity 5052, and one end of the ring coil 5053 passes through the outer wall of the loading block 5041 and is electrically connected to the outside.

[0055] The ring coil 5053 in this invention is not a simple planar ring, but rather arranged in a three-dimensional wave-like pattern along the annular space of the magnetocontrol cavity 5052. This structural design maximizes the effective conductor length of the coil within a limited space, and when a control current is applied, it can generate a stronger magnetomotive force and a more concentrated magnetic flux.

[0056] During operation, the strong magnetic field generated by the ring coil 5053 penetrates vertically through the damping cavity 5042 above, providing comprehensive, efficient, and uniform magnetization control of the magnetorheological fluid within the cavity. One end of the coil protrudes from the outer wall of the loading block 5041, ensuring a reliable and convenient connection to the external control circuit and facilitating the reception of real-time control signals. The ability to simulate a continuous spectrum of loads, from instantaneous rigid impacts to slow, flexible loading, using a single impact is one of the core technical features of this device, enabling its intelligent and programmable capabilities and effectively enhancing the realism and evaluation value of the test.

[0057] Working principle: This embodiment provides a method for using a sunroof bracket impact resistance testing device, including the following steps: S1. Clamping and positioning; The sunroof bracket and glass to be tested are securely installed on the load platform 1 using the tooling fixture 2. The hydraulic mechanism 3 is activated, its output end height is adjusted, and the horizontal position is finely adjusted by the pitch mechanism 4 so that the multi-mode impact mechanism 5 set at the output end of the pitch mechanism 4 is precisely aligned with the test area of ​​the sunroof bracket. S2, Impact Mode Selection and Execution; According to the test requirements, select the operating mode of gradient module 502 and control the impact application method through it: S2.1, Dynamic Diffusion Impact Mode; The power source 5021 of the gradient module 502 is activated, driving the power rod 5022 and the rack 5023 fixed thereon to rotate. By sequentially deflecting several rings 5024 sleeved on the rack 5023 and contact rings 5025 fixed thereon, the continuous rotational motion of the rack 5023 is converted into intermittent lifting motion of each contact ring 5025 reaching its peak in a time sequence. Each contact ring 5025 sequentially pushes the corresponding movable rigid rod 5031 with a contact ball head 5032, causing the movable rigid rod 5031 to move axially along the movable hole 5015 at the bottom of the dynamic box 501. Each movable rigid rod 5031 drives several load blocks 5041 fixedly connected to it and nested in gradient sizes to move sequentially, thereby forming a dynamic impact area on the test surface, starting from the smallest load block in the center and expanding outward to larger load blocks, simulating the diffusion process of shock waves. S2.2, Multi-point constant impact mode; The gradient module 502 is locked in one of at least two different preset radius positions. At this time, one or more rings 5024 and their contact rings 5025 corresponding to a specific radius are fixed in the drive position. One or more movable rigid bars 5031 corresponding to this locked position and their connected loading blocks 5041 are preset to a trigger-ready state. S3, Instantaneous impact loading; After completing the preparation for mode S2.1 or S2.2, the output end of the control hydraulic mechanism 3 is rapidly pressed down, and the entire multi-mode impact mechanism 5 is instantly pressed down at a set speed and energy through the pitch mechanism 4, applying the main instantaneous impact force to the sunroof bracket; during this process: In the dynamic diffusion impact mode S2.1, the hydraulic impact is combined with the time-sequential drive of the gradient module 502, so that the impact force is dynamically applied in space according to the preset gradient. In the multi-point constant impact mode S2.2, the hydraulic impact causes all the load blocks 5041 in the ready-to-trigger state to press down synchronously, applying a multi-point constant impact force corresponding to the selected radius to the support. S4. Real-time adjustment of impact stiffness; During the impact loading process of S3, stiffness adjustment can be performed synchronously. By controlling the stiffness execution unit 505 built into the loading block 5041, specifically by passing a controllable current into the ring coil 5053, a magnetic field is excited in the magnetic control cavity 5052. This magnetic field acts on the magnetorheological fluid in the damping cavity 5042, instantaneously changing its rheological properties, thereby dynamically adjusting the motion damping of the buffer ring 5043 during the impact, realizing real-time and programmable control of the impact stiffness and waveform of a single impact, so as to simulate the impact characteristics of falling objects of different hardness, such as stones or hail. S5. Data Acquisition and Reset; Force and displacement sensors installed on the load platform 1 or tooling fixture 2 collect data such as force, displacement, and strain during the impact process to evaluate the impact resistance of the sunroof bracket. After the test is completed, the hydraulic mechanism 3 drives the multi-mode impact mechanism 5 to reset, ready for the next test.

[0058] The embodiments disclosed in this invention are preferred embodiments, but are not limited thereto. Those skilled in the art can easily understand the spirit of this invention based on the above embodiments and make different extensions and variations, but as long as they do not depart from the spirit of this invention, they are all within the protection scope of this invention.

Claims

1. A test device for the impact resistance of a sunroof bracket, characterized in that, It includes a load platform (1), tooling fixtures (2), hydraulic mechanism (3), pitch mechanism (4), and multi-mode impact mechanism (5); The tooling fixture (2) is set on the load platform (1) for fixing the sunroof bracket to be tested; The hydraulic mechanism (3) is located at the top of the load platform (1), and the variable pitch mechanism (4) is suspended at its output end. The multi-mode impact mechanism (5) is located at the output end of the variable pitch mechanism (4) and includes a dynamic box (501), a gradient module (502), a rigid bar group (503), a loading component (504), and a stiffness execution unit (505). The dynamic box (501) is fixed at the output end of the pitch mechanism (4); The gradient module (502) is disposed inside the dynamic box (501); The rigid bar assembly (503) is movably disposed inside the dynamic box (501), with one end connected to the gradient module (502) and the other end extending out of the dynamic box (501) and fixedly connected to the loading component (504). The stiffness actuation unit (505) is built into the loading assembly (504). The gradient module (502) is configured to selectively drive the rigid bar assembly (503) to actuate so that the loading component (504) achieves a dynamic impact that expands gradually from the center to the periphery; or, the gradient module (502) can be selectively locked at at least two different preset radius positions so that the loading component (504) achieves a constant impact corresponding to the selected radius.

2. The impact resistance testing device for a sunroof bracket according to claim 1, characterized in that, The dynamic box (501) includes a box body (5011), a dynamic chamber (5012), a partition (5013), and a movable chamber (5014). The box body (5011) is fixedly connected to the output end of the variable pitch mechanism (4). The dynamic chamber (5012) is opened at the top inside the box body (5011). The partition (5013) is fixedly disposed at the bottom inside the box body (5011). The movable chamber (5014) is disposed between the bottom of the box body (5011) and the partition (5013). The gradient module (502) is disposed in the dynamic chamber (5012). The rigid rod group (503) is movably inserted into the partition (5013), the movable chamber (5014), and the bottom of the box body (5011).

3. The impact resistance testing device for a sunroof bracket according to claim 2, characterized in that, The bottom of the partition (5013) and the box (5011) are provided with movable holes (5015) at equal intervals in a linear shape, and the rigid rod group (503) is movably inserted into the movable holes (5015).

4. The impact resistance testing device for a sunroof bracket according to claim 1, characterized in that, The gradient module (502) includes a power source (5021), a power rod (5022), a rack (5023), a ring sleeve (5024), and a contact ring (5025). The power source (5021) is fixedly installed on the outer wall of the dynamic box (501). One end of the power rod (5022) is fixedly connected to the output end of the power source (5021), and the other end of the power rod (5022) is rotatably inserted into the dynamic box (501). The rack (5023) is fixedly connected to the power rod (5022). Several ring sleeves (5024) are sequentially deflected and sleeved on the rack (5023). The contact ring (5025) is fixedly sleeved on the ring sleeves (5024).

5. The impact resistance testing device for a sunroof bracket according to claim 4, characterized in that, The inner wall of the ring (5024) is provided with a protrusion (5026), and the protrusion (5026) is provided with a toothed hole (5027) that is adapted to the toothed rod (5023). A plurality of the rings (5024) are sequentially deflected onto the toothed rod (5023) through the toothed hole (5027) on the protrusion (5026).

6. The impact resistance testing device for a sunroof bracket according to claim 1, characterized in that, The rigid rod assembly (503) includes movable rigid rods (5031) and contact ball heads (5032). A plurality of movable rigid rods (5031) are movably inserted into the bottom end of the dynamic box (501). The bottom end of the movable rigid rods (5031) is fixedly connected to the load application assembly (504). The contact ball heads (5032) are rotatably disposed on the movable rigid rods (5031). The end of the contact ball head (5032) away from the movable rigid rods (5031) is movably connected to the gradient module (502).

7. The impact resistance testing device for a sunroof bracket according to claim 1, characterized in that, The loading assembly (504) includes a plurality of loading blocks (5041) that are movably nested together and whose size increases or decreases, and the plurality of loading blocks (5041) are connected to the bottom end of the rigid rod assembly (503).

8. The impact resistance testing device for a sunroof bracket according to claim 7, characterized in that, The top of the loading block (5041) is provided with a damping cavity (5042), and a buffer ring (5043) is slidably provided on the damping cavity (5042). The end of the rigid rod assembly (503) away from the dynamic box (501) is fixedly connected to the buffer ring (5043), and the damping cavity (5042) is provided with magnetorheological fluid.

9. The impact resistance testing device for a sunroof bracket according to claim 8, characterized in that, The stiffness actuation unit (505) includes a bottom ring plate (5051), a magnetic control cavity (5052), and a ring wave coil (5053). The bottom ring plate (5051) is fixedly disposed at the bottom end of the loading block (5041). The magnetic control cavity (5052) is opened between the bottom ring plate (5051) and the bottom end of the inner wall of the loading block (5041). The ring wave coil (5053) is disposed in the magnetic control cavity (5052).

10. The impact resistance testing device for a sunroof bracket according to claim 9, characterized in that, The ring wave coil (5053) is arranged in a ring-shaped wave pattern inside the magnetocontrol cavity (5052), and one end of the ring wave coil (5053) passes through the outer wall of the loading block (5041) and is electrically connected to the outside.

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