A dual arm fall tester

Abstract

The application discloses a double-arm drop tester, and relates to the field of drop tests, which comprises a double-arm drop tester body, a film test table arranged at the bottom, a fixing clamp suspended on the double-arm drop tester, and an adjusting unit arranged on the fixing clamp; a spherical bearing is fixedly arranged at the end of the fixing clamp; the adjusting unit comprises a spherical seat hinged with the spherical bearing, and an annular track fixedly arranged at the bottom of the spherical seat; three clamping arms for positioning workpieces are slidingly arranged on the annular track, and are respectively a first clamping arm, a second clamping arm and a third clamping arm. The double-arm drop tester simultaneously realizes the contraction locking of the adhering suction disc and the posture locking of the spherical bearing, and has a simple structure; the protective film presents a concave structure when moving downward along with the impact table, the concave protective film can buffer and gather the scattered parts, and the problem that the parts are scattered everywhere on the existing rigid test table and are difficult to collect and analyze is solved.

Description

Technical Field

[0001] This invention relates to the field of drop testing technology, and more specifically to a double-arm drop testing machine. Background Technology

[0002] Drop testing machines are critical testing equipment used to simulate accidental drops of products during transportation, handling, or use. They are widely used in industries such as electronics, packaging materials, home appliances, and medical devices. Drop tests can assess the impact resistance of a product's structure, identify design flaws, and provide a basis for product improvement. Among these, the dual-arm drop testing machine is one of the most common drop testing devices in laboratories due to its stable structure, smooth lifting, and controllable drop posture.

[0003] Existing double-arm drop test machines typically include a liftable double-arm suspension mechanism and fixed clamps at the ends of the suspension. During testing, the operator clamps the workpiece to be tested onto the clamps, raises it to a predetermined height, and then releases it, allowing the workpiece to fall freely onto the test platform below.

[0004] A drop test protection device for a drop machine, disclosed in Chinese Patent CN211740550U, includes a base. The top of the base has a mounting groove, within which a drop panel is slidably mounted. The top of the drop panel extends beyond the mounting groove and is fixedly mounted on a drop machine. A support column is fixedly mounted on the inner wall of the bottom of the mounting groove. The bottom of the drop panel has a first sliding groove, within which the top of the support column is slidably mounted and fixedly mounted with a first shock-absorbing pad. A first spring is fixedly mounted on the top of the first shock-absorbing pad. This design is reasonable and practical, effectively buffering and damping the vibration force generated when an object falls freely onto the drop panel, preventing damage to the drop panel from prolonged exposure to the force of falling objects. Furthermore, it significantly reduces the transmission of vibration force from the drop panel to the drop machine, effectively protecting both the drop panel and the drop machine.

[0005] However, the drop test benches mentioned above use cushioning pads only to protect the panel. After receiving a workpiece, the springs on these pads are prone to releasing their stored force, causing the workpiece to bounce, tumble, or even experience multiple impacts. This not only causes unexpected secondary damage to the workpiece, but more seriously, the broken parts scatter in all directions, making them difficult to collect. When faced with workpieces missing parts or those that have undergone multiple impacts, failure analysts often find it difficult to accurately determine the initial fracture location, crack propagation path, and the true cause of failure, severely impacting the reliability of failure analysis and the correctness of improvement decisions. Summary of the Invention

[0006] The purpose of this invention is to provide a double-arm drop test machine to solve the above-mentioned problems.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a double-arm drop test machine, comprising a double-arm drop test machine body and a film-coated test platform disposed at the bottom, wherein a fixing clamp is suspended on the double-arm drop test machine, and an adjustment unit disposed on the fixing clamp is also included. A spherical bearing fixedly mounted at the end of a fixed clamp; The adjustment unit includes a spherical seat hinged to a spherical bearing, and an annular track fixedly disposed at the bottom of the spherical seat. Three clamping arms for positioning the workpiece are slidably disposed on the annular track, namely a first clamping arm, a second clamping arm, and a third clamping arm. The first clamping arm, the second clamping arm, and the third clamping arm are all provided with a contact suction cup, and also include a cylinder for driving the angle of the contact suction cup to change; The fitting suction cup includes a corrugated tubular rubber bladder filled with hydraulic oil, and the spherical bearing is provided with a valve structure that can expand radially under oil pressure, and the valve structure moves synchronously with the corrugated tubular rubber bladder. The coating test bench includes an impact platform maintained at a predetermined height and a protective film, and the protective film forms a recessed structure for protecting the workpiece as the impact platform moves downward.

[0008] Preferably, the impact table is equipped with a visual recognition sensor at its center for detecting the position of the workpiece.

[0009] Preferably, the film coating test bench also includes a base; The impact table is slidably mounted on the center of the base, and a diagonal rod is fixedly mounted on the lower end of the impact table; A sliding plate is slidably disposed inside the base, and a third spring is disposed at the bottom of the sliding plate. A wedge block for pressing the sliding plate to a lower position is slidably disposed inside the base, and a support assembly is disposed on the sliding plate.

[0010] Preferably, the support assembly includes a first baffle and a second baffle hinged to the sliding plate, and both the first baffle and the second baffle are provided with torsion springs; It also includes a drive motor for changing the angle between the first baffle and the second baffle.

[0011] Preferably, the base is rotatably provided with a cam that abuts against the first baffle and is slidably provided with a slide rod; During the three rotational strokes of the trigger rod, the cam has three corresponding positions, which respectively drive the first baffle and the second baffle to switch to a rectangular surface, parallel sides, and radial tensioning form.

[0012] Preferably, it also includes a trigger rod for driving the first clamping arm, the trigger rod being rotatably disposed at the bottom of the spherical seat; A main gear is fixedly installed on the trigger rod, and a limiting plate that can engage the second clamping arm and the third clamping arm is slidably installed on the second end of the trigger rod. The limiting plate is provided with a protrusion. The annular track is provided with a guide slope for guiding the protrusion, and the limiting plate is kept extended by a first elastic element; The ball seat also has a half gear and a mating gear rotatably mounted at its bottom. The half gear is fixedly connected to the third clamping arm, and the mating gear can mesh with the main gear and the half gear respectively.

[0013] Preferably, the mating gear includes a large gear at the upper end and a small gear at the lower end.

[0014] Preferably, the guide slope is an arc-shaped protrusion extending circumferentially, with its starting end offset from the protrusion in the circumferential direction.

[0015] Preferably, the transmission ratio of the main gear and the half gear is 1:3.

[0016] Preferably, the protective film is made of polyurethane elastomer.

[0017] In the above technical solution, the double-arm drop test machine provided by the present invention has the following beneficial effects: the device simultaneously realizes the shrinkage and locking of the suction cup and the posture locking of the ball bearing, and the structure is simple; the protective film presents a concave structure as the impact table moves down, and the concave protective film can both buffer and gather scattered parts, solving the problem of parts splashing everywhere on the existing rigid test table and being difficult to collect and analyze. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0019] Figure 1 This is a schematic diagram of the overall structure provided for an embodiment of the present invention; Figure 2 This is a schematic diagram of the cross-sectional structure of a spherical bearing provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the adjustment unit structure provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of another angle structure of the adjustment unit provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the clamping arm and corrugated tubular rubber bladder structure provided in an embodiment of the present invention; Figure 6This is a schematic diagram of the cross-sectional structure of the base provided in an embodiment of the present invention; Figure 7 A schematic diagram of the support component structure provided in an embodiment of the present invention; Figure 8 This is a schematic diagram of the surface drop test bench structure provided in an embodiment of the present invention; Figure 9 This is a schematic diagram of the edge drop test bench structure provided in an embodiment of the present invention; Figure 10 This is a schematic diagram of the corner drop film coating test bench provided in an embodiment of the present invention; Figure 11 This is a schematic diagram of the surface drop adjustment unit structure provided in an embodiment of the present invention; Figure 12 This is a schematic diagram of the edge drop adjustment unit structure provided in an embodiment of the present invention; Figure 13 This is a schematic diagram of the angle drop adjustment unit structure provided in an embodiment of the present invention.

[0020] Explanation of reference numerals in the attached figures: 100. Coating test bench; 110. Base; 120. Impact table; 121. Second spring; 122. Diagonal bar; 130. Support assembly; 131. First baffle; 132. Second baffle; 140. Sliding plate; 141. Third spring; 150. Wedge; 160. Protective film; 170. Cam; 180. Sliding rod; 200. Fixing clamp; 210. Ball bearing; 211. Radial blind hole; 212. Valve structure; 300. Adjustment unit; 310. Spherical seat; 32. 0. Counterweight bar; 330. Circular track; 331. Guide slope; 341. First clamping arm; 342. Second clamping arm; 343. Third clamping arm; 350. Trigger rod; 351. Limiting plate; 352. Protrusion; 353. First elastic element; 360. Main gear; 370. Half gear; 380. Matching gear; 390. Adhesive suction cup; 391. Corrugated tubular rubber bladder; 392. Pneumatic suction cup; 400. Cylinder; 500. Miniature diaphragm pump; 600. Visual recognition sensor. Detailed Implementation

[0021] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0022] like Figure 1-8 As shown, a double-arm drop test machine includes a double-arm drop test machine body and a film-coated test platform 100 provided at the bottom. A fixing clamp 200 is suspended on the double-arm drop test machine, and an adjustment unit 300 is also provided on the fixing clamp 200. A ball bearing 210 is fixedly mounted at the end of the fixing clamp 200; The adjustment unit 300 includes a ball seat 310 hinged to the ball bearing 210, and an annular track 330 fixedly disposed at the bottom of the ball seat 310. Three clamping arms for positioning the workpiece are slidably disposed on the annular track 330, namely the first clamping arm 341, the second clamping arm 342 and the third clamping arm 343. The first clamping arm 341, the second clamping arm 342 and the third clamping arm 343 are each provided with a bonding suction cup 390, and also include a cylinder 400 for driving the bonding suction cup 390 to change angle. The suction cup 390 includes a bellows-shaped rubber bladder 391 filled with hydraulic oil, and a valve structure 212 that can expand radially under oil pressure is provided in the ball bearing 210, and the valve structure 212 and the bellows-shaped rubber bladder 391 move synchronously. The coating test bench 100 includes an impact table 120 held at a predetermined height and a protective film 160, wherein the protective film 160 forms a recessed structure for protecting the workpiece as the impact table 120 moves downward.

[0023] Specifically, the spherical bearing 210 has a radial blind hole 211, and the valve structure 212 is located at the end of the radial blind hole 211 facing the spherical seat 310, such as... Figure 2 As shown. The inner ring of the spherical bearing 210 is fixedly connected to the fixed clamp 200, and the outer ring is hinged to the spherical seat 310, allowing the spherical seat 310 to swing freely within a certain angle range. The counterweight rod 320 is fixed above the spherical seat 310 and extends upward through the spherical bearing 210. When the workpiece is clamped, the counterweight rod 320 and the workpiece are equivalent to a pendulum.

[0024] Furthermore, each of the three clamping arms—the first clamping arm 341, the second clamping arm 342, and the third clamping arm 343—is equipped with a slider at its base, which is slidably fitted into the annular track 330 at the bottom of the spherical seat 310. The annular track 330 is a complete circular groove, within which the three clamping arms can slide freely to change the angle between them. The clamping arms can be set manually: the operator can directly move any clamping arm by hand to move it along the annular track 330, and simultaneously fix the adjusted position through a linkage mechanism or friction locking device (using existing technology such as locking screws, which are prior art and will not be described in detail here).

[0025] The corrugated rubber bladder 391 is an axially expandable corrugated structure, its interior sealed and filled with hydraulic oil. A pneumatic suction cup 392 is fixed to the bottom of the corrugated rubber bladder 391 and generates negative pressure via an external air source to adsorb the workpiece surface. The cylinder body of the cylinder 400 is hinged to the middle of the clamping arm, and the end of its piston rod is hinged to the side of the suction cup 390. When the cylinder 400 extends or retracts, it drives the suction cup 390 to swing around its connection point with the clamping arm, thereby changing the adsorption angle to adapt to the normal direction of the workpiece surface.

[0026] Before clamping the workpiece, the operator manually adjusts the positions of the three clamping arms on the annular track 330 according to the workpiece's geometry, ensuring they are roughly distributed around the workpiece. Then, the air source is activated, creating negative pressure in the pneumatic suction cup 392 to initially attract the workpiece. At this time, due to the presence of the ball bearing 210, the ball seat 310 can swing freely, while the corrugated rubber bladder 391, filled with hydraulic oil, is in a flexible state. Therefore, the contact suction cup 390 can automatically adapt to the slight undulations and tilts of the workpiece surface, achieving complete contact.

[0027] Once the workpiece is in the correct position, it needs to be locked to prevent it from swaying during the drop. The operator can apply pressure to the system using a manual hydraulic pump. The outlet of this pump is connected via piping to three corrugated rubber bladders 391 and the valve structure 212 within the spherical bearing 210. When the operator presses the pump, hydraulic oil is forced into the chambers of the corrugated rubber bladders 391 and the valve structure 212. Due to the limited volume of the corrugated rubber bladders 391 and their corrugated structure expanding outwards and contracting axially under hydraulic pressure, the bladders harden and shorten, thus tightly pulling the pneumatic suction cup 392 towards the workpiece surface, achieving rigid locking. Simultaneously, under hydraulic pressure, the valve structure 212's multiple elastic valves expand radially outwards, tightly pressing against the inner spherical surface of the spherical bearing 210, thereby locking the spherical seat 310 in its current position, preventing further swaying. Through a hydraulic operation, the suction cup retraction and locking, and the ball joint attitude locking are simultaneously achieved, with both remaining completely synchronized. After locking is completed, the operator activates the release mechanism of the double-arm drop test machine body, and the fixed clamp 200 is released instantly, allowing the workpiece to fall freely along with the adjustment unit 300.

[0028] The protective film test bench 100 is located directly below the drop point. In the initial state, the impact bench 120 is supported at a predetermined height (e.g., 50 mm from the bottom surface of the base) by the second spring 121. The protective film 160 is made of polyurethane elastomer, and the center of the protective film 160 is fixedly connected to the upper end face of the impact bench 120 by screws or retaining rings. In the initial state, the protective film 160 is in a relaxed, flat state, without providing any cushioning effect.

[0029] When the workpiece falls and impacts the upper surface of the impact table 120, the enormous impact force overcomes the elastic force of the second spring 121, forcing the impact table 120 to move rapidly downwards. Since the center of the protective membrane 160 is fixed to the impact table 120, while its four corners are fixed to stationary supports, as the impact table 120 moves downwards, the center of the protective membrane 160 is pulled downwards, while the four corners remain stationary, thus forming a flexible "pocket-shaped" or "bowl-shaped" structure. This raised protective membrane 160 precisely catches the workpiece and its parts that may bounce or scatter after the fall. The flexible material of the protective membrane 160 can absorb most of the remaining impact energy, preventing the workpiece from bouncing again; at the same time, the raised pocket-shaped structure can gather scattered parts in the central area, preventing them from splashing outwards.

[0030] In the above technology, the shrinkage and locking of the suction cup 390 and the attitude locking of the ball bearing 210 are achieved simultaneously, and the structure is simple. The protective film 160 presents a concave structure as the impact table 120 moves down. The concave protective film 160 can both buffer and gather scattered parts, solving the problem of parts splashing everywhere on the existing rigid test table and being difficult to collect and analyze.

[0031] As a further embodiment of the present invention, a visual recognition sensor 600 for detecting the position of the workpiece is provided at the center of the impact table 120.

[0032] Specifically, the visual recognition sensor 600 can be a CCD camera or a laser rangefinder with its lens facing upwards, used to identify the bottom contour of the clamped workpiece.

[0033] Furthermore, a miniature diaphragm pump 500 is connected between the radial blind hole 211 and the corrugated tubular rubber bladder 391, such as... Figure 7 As shown. The output of the visual recognition sensor 600 is electrically connected to the input of the control module, and the output of the control module is electrically connected to the drive circuit of the micro diaphragm pump 500. After the adjustment unit 300 clamps the workpiece and adjusts it to a predetermined posture, the visual recognition sensor 600 collects the positional deviation of the bottom center of the workpiece relative to the center of the impact table 120 in real time. If the center of the workpiece is aligned with the center of the impact table 120, the control module sends a signal to trigger the micro diaphragm pump 500 to operate, drawing hydraulic oil from the corrugated rubber bladder 391 into the radial blind hole 211, causing the suction cup 390 to contract and harden and lock the spherical seat 310. If it is not aligned, the control module does not trigger, and the adjustment unit 300 can continue to fine-tune the workpiece position.

[0034] As a further embodiment of the present invention, the film coating test bench 100 also includes a base 110; an impact table 120 is slidably disposed at the center of the base 110, and a diagonal rod 122 is fixedly disposed at the lower end of the impact table 120; a sliding plate 140 is slidably disposed inside the base 110, and a third spring 141 is disposed at the bottom of the sliding plate 140; a wedge block 150 for pressing the sliding plate 140 to a lower position is slidably disposed inside the base 110; and a support assembly 130 is disposed on the sliding plate 140.

[0035] Specifically, a second spring 121 is provided on the impact table 120. The base 110 is a square box structure with a vertical guide hole in the center. The lower guide post of the impact table 120 is slidably fitted into this guide hole. The sliding plate 140 consists of four independent plates, located at the four corners of the base 110. The upper end of the third spring 141 abuts against the lower surface of the sliding plate 140, and the lower end abuts against the bottom plate of the base 110, always pushing the sliding plate 140 upward. In the initial state, the wedge block 150 is in an extended position under the constraint of the inclined rod 122, with its outer end abutting against the inner wall of the sliding plate 140, overcoming the elastic force of the third spring 141 and pressing the sliding plate 140 into a low position. The support assembly 130 is installed on the upper surface of the sliding plate 140. When the workpiece falls and impacts the impact table 120, the impact table 120 moves downward, and the inclined surface of the inclined bar 122 presses down on the inclined surface of the wedge block 150, forcing all the wedge blocks 150 to retract radially towards the center of the base 110, thereby relieving the pressure on the sliding plate 140. The sliding plate 140, pushed by the third spring 141, quickly springs upward, causing the support assembly 130 to rise. During the upward movement of the support assembly 130, it supports the four corners of the protective film 160 upward, causing the protective film 160 to form raised buffer pockets.

[0036] As a further embodiment of the present invention, the support assembly 130 includes a first baffle 131 and a second baffle 132 hinged to the sliding plate 140, and both the first baffle 131 and the second baffle 132 are provided with torsion springs; it also includes a drive motor for driving the angle between the first baffle 131 and the second baffle 132 to change.

[0037] Specifically, the two are hinged to the sliding plate 140 via a hinge shaft, on which a torsion spring is fitted. The preload of the torsion spring maintains the first baffle 131 and the second baffle 132 at a perpendicular angle in their free state. A drive motor is mounted on the upper surface of the base 110. The rotation of the drive motor can drive the first baffle 131 to deflect, thereby changing the angle between the first baffle 131 and the second baffle 132. When the angle is 90°, the four support assemblies 130 form a rectangle, and during ascent, the protective membrane 160 is stretched along the four corners to form a flat buffer surface (e.g., ...). Figure 8As shown, the tensioning direction is as indicated by the arrow; when the included angle is 180°, i.e., when the two are parallel, the support assembly 130 only tensions the protective membrane 160 in two directions, forming a V-shaped buffer groove (as shown). Figure 9 As shown, the tensioning direction is indicated by the arrows; when the included angle is 150°, the support assembly 130 forms an approximate dodecagon, and the protective membrane 160 is stretched radially to form a three-dimensional buffer space (as shown). Figure 10 As shown in the diagram, the tensioning direction is indicated by the arrow. The drive motor actively controls the baffle angle, enabling the film-coating test bench 100 to adaptively change the tensioning shape of the protective film 160 according to the different drop postures (face, edge, corner) of the workpiece, achieving the optimal buffering effect and preventing the workpiece from rolling over again during the drop due to mismatch with the protective film 160.

[0038] As a further embodiment of the present invention, a cam 170 that abuts against the first baffle 131 is rotatably provided on the base 110 and a slide rod 180 is slidably provided on it; During the three rotational strokes of the trigger rod 350, the cam 170 has three corresponding positions, which respectively drive the first baffle 131 and the second baffle 132 to switch to rectangular surface, parallel side and radial tensioning form.

[0039] Specifically, a cam 170 is provided on the upper surface of the base 110 near each support assembly 130. The cams 170 are synchronously rotated by the same drive motor via a synchronous belt or gear transmission. The profile of the cam 170 has three angular positions: the first angular position is when the base circle of the cam 170 contacts the first baffle 131, at which point the first baffle 131 maintains an initial 90° angle under the action of a torsion spring, corresponding to a rectangular tensioned shape; the second angular position is when the cam 170 rotates 180°, and its protrusion pushes the slide rod 180 to slide along the Y-axis (where the Y-axis is as follows). Figure 9As shown in the direction (i.e., in the test edge state, the Y-axis is parallel to the test edge), the end of the slide rod 180 presses against the second baffle 132, causing it to deflect by 90°, thus making the first baffle 131 and the second baffle 132 parallel, corresponding to the parallel edge tensioning state; the third angle position is when the cam 170 continues to rotate 90° for a total of 270°. At this time, the protrusion of the cam 170 directly presses against the first baffle 131, causing the first baffle 131 to deflect, while the second baffle 132 swings back a certain angle under the action of the torsion spring, finally making the included angle between the two 150°, corresponding to the radial tensioning state. The rotation of the drive motor and the rotation of the trigger rod 350 are linked through the control module. That is, when the operator rotates the trigger rod 350 to the surface drop position, the drive motor automatically drives the cam 170 to the first angle position; when rotating to the edge drop position, the cam 170 automatically rotates to the second angle position; when rotating to the corner drop position, the cam 170 automatically rotates to the third angle position. Synchronous switching is achieved, eliminating the need for operators to manually adjust the test bench, greatly improving testing efficiency. The film-coated test bench 100 can adaptively change the tension of the protective film 160 according to the different drop postures, edges, and corners of the workpiece, achieving the optimal buffering effect. This prevents the workpiece from rolling over again during the drop due to mismatch with the protective film 160, and avoids test failures caused by forgetting to adjust the buffering shape.

[0040] As a further embodiment of the present invention, it also includes a trigger rod 350 for driving the first clamping arm 341, the trigger rod 350 being rotatably disposed at the bottom of the ball seat 310; A main gear 360 is fixedly installed on the trigger rod 350, and a limiting plate 351 that can engage the second clamping arm 342 and the third clamping arm 343 is slidably installed on the second end of the trigger rod 350. A protrusion 352 is provided on the limiting plate 351. The annular track 330 is provided with a guide slope 331 for guiding the protrusion 352, and the limiting plate 351 is kept extended by the first elastic member 353; The ball seat 310 is also rotatably provided with a half gear 370 and a mating gear 380 at its bottom. The half gear 370 is fixedly connected to the third clamping arm 343, and the mating gear 380 can mesh with the main gear 360 and the half gear 370 respectively.

[0041] Specifically, such as Figure 3 and Figure 4As shown, the mating gear 380 includes a large gear at the upper end and a small gear at the lower end, with a clearance between them to allow for small relative rotation. This allows the small gear to adaptively deflect during meshing with the half gear 370. The transmission ratio between the main gear 360 and the half gear 370 is 1:3. The trigger rod 350 is coaxially mounted with the ball seat 310, with its first end fixedly connected to the first clamping arm 341 and its second end slidably mounted with a limit plate 351. The limit plate 351 has a slot at its outer end to engage the second clamping arm 342 and the third clamping arm 343. A first elastic element 353 is provided on the limit plate, and the engagement is maintained under the action of the first elastic element 353, allowing the three clamping arms to rotate synchronously with the trigger rod 350. When the trigger rod 350 rotates, if the protrusion 352 does not contact the guide slope 331, the limit plate 351 remains extended, and the three clamping arms rotate synchronously. When the protrusion 352 slides onto the guide slope 331, the guide slope 331 compresses the protrusion 352, thereby causing the limiting plate 351 to retract inward against the first elastic element 353, so that the limiting plate 351 disengages from the second clamping arm 342 and the third clamping arm 343.

[0042] The main gear 360 is fixed to the trigger rod 350 and is rotatably mounted on the bottom of the ball seat 310 in conjunction with the gear 380 and located on the initial radial line of the first clamping arm 341. The half gear 370 is fixedly connected to the third clamping arm 343.

[0043] The overall workflow is as follows: Initial to edge mode (trigger rod 350 rotates 90° clockwise): During the initial stroke, the protrusion 352 does not contact the guide slope 331, and the three clamping arms rotate synchronously. At this time, the extension of the cylinder 400 is at its longest, and the bottom ends of multiple contact suction cups 390 are on the same plane for contacting the workpiece surface. When the protrusion 352 slides onto the guide slope 331, the limiting plate 351 is pushed back inward, disengaging from the second clamping arm 342 and the third clamping arm 343. At this time, the second clamping arm 342 stops rotating, and the lower gear of the engaging gear 380 meshes with the half gear 370, but the half gear 370 has not yet been driven. The extension of the cylinder 400 retracts, so that the suction cups of the first clamping arm 341 and the suction cups of the second and third clamping arms 342 form a 90-degree angle for contacting the edge of the workpiece. In this state, it can ensure that the edge of the workpiece is clamped is parallel to the Y-axis of the base 110.

[0044] From edge mode to corner mode (trigger rod 350 rotates another 30°, totaling 120°): The main gear 360 rotates 30° with the trigger rod 350, driving the half gear 370 to rotate 90° through the mating gear 380 at a 1:3 transmission ratio. The rotation of the main gear 360 is transmitted to the half gear 370 through the mating gear 380. Since the mating gear 380 only acts as an idler gear and does not change the overall transmission ratio, the total angular velocity ratio between the main gear 360 and the half gear 370 is 1:3, that is, when the main gear 360 rotates 1°, the half gear 370 rotates 3°. The third clamping arm 343 then rotates an additional 90° relative to the annular track 330, ultimately forming a 120° angle with the fixed first clamping arm 341 and second clamping arm 342, constituting a three-point support for clamping the top corner of the workpiece. Furthermore, the posture adjustment of the clamping arms and the position adjustment of the support assembly 130 are synchronized through the control module. Simply rotating the trigger lever 350 clockwise twice (90° → then 30°) drives the three clamping arms to precisely switch between three postures: "face clamping," "edge clamping," and "corner clamping." When the operator rotates the trigger lever 350 to select different drop modes, the control module automatically drives the support assembly 130 of the film-coated test bench 100 to switch to the corresponding tensioning shape (rectangular face, parallel sides, or radial shape). This effectively supports workpiece components that break apart during the drop, preventing them from scattering or being lost. This allows failure analysts to collect complete part fragments, accurately determine the fracture location, crack origin, and failure path, and avoid misjudgments due to missing parts. Secondly, the flexible buffering characteristics of the protective film 160 prevent the workpiece from bouncing and impacting multiple times on the rigid platform, ensuring that the damage to the workpiece originates only from the initial drop impact. This makes the failure mode clearer and facilitates tracing the root cause. The synchronous linkage between the clamping arm and the buffer configuration ensures that the posture and impact conditions remain highly consistent in each drop test, resulting in good repeatability. This provides a reliable data basis for comparing the failure characteristics of different batches or different design schemes, improving the efficiency and reliability of failure analysis.

[0045] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A double-arm drop test machine, comprising a double-arm drop test machine body and a film-coated test platform (100) disposed at the bottom, wherein a fixing clamp (200) is suspended on the double-arm drop test machine, characterized in that, It also includes an adjustment unit (300) disposed on the fixed clamp (200); A ball bearing (210) is fixedly mounted on the end of the fixed clamp (200); The adjustment unit (300) includes a spherical seat (310) hinged to a spherical bearing (210) and an annular track (330) fixedly disposed at the bottom of the spherical seat (310). Three clamping arms for positioning the workpiece are slidably disposed on the annular track (330), namely a first clamping arm (341), a second clamping arm (342) and a third clamping arm (343). The first clamping arm (341), the second clamping arm (342) and the third clamping arm (343) are each provided with a suction cup (390), and also include a cylinder (400) for driving the angle of the suction cup (390) to change. The fitting suction cup (390) includes a corrugated tubular rubber bladder (391) filled with hydraulic oil, and the ball bearing (210) is provided with a valve structure (212) that can expand radially under oil pressure, and the valve structure (212) and the corrugated tubular rubber bladder (391) move synchronously. The coating test bench (100) includes an impact table (120) held at a predetermined height and a protective film (160), and the protective film (160) forms a recessed structure for protecting the workpiece as the impact table (120) moves down.

2. The double-arm drop test machine according to claim 1, characterized in that, The impact table (120) is equipped with a visual recognition sensor (600) at its center for detecting the position of the workpiece.

3. The double-arm drop test machine according to claim 1, characterized in that, The film coating test bench (100) also includes a base (110); The impact table (120) is slidably disposed at the center of the base (110), and a diagonal rod (122) is fixedly disposed at the lower end of the impact table (120). A sliding plate (140) is slidably disposed inside the base (110), and a third spring (141) is disposed at the bottom of the sliding plate (140). A wedge (150) for pressing the sliding plate (140) to a low position is slidably disposed inside the base (110), and a support assembly (130) is disposed on the sliding plate (140).

4. The double-arm drop test machine according to claim 3, characterized in that, The support assembly (130) includes a first baffle (131) and a second baffle (132) hinged to the sliding plate (140), and both the first baffle (131) and the second baffle (132) are provided with torsion springs; It also includes a drive motor for driving the angle between the first baffle (131) and the second baffle (132) to change.

5. A double-arm drop test machine according to claim 4, characterized in that, The base (110) is rotatably provided with a cam (170) that abuts against the first baffle (131) and is slidably provided with a slide rod (180). During the three rotational strokes of the trigger rod (350), the cam (170) has three corresponding positions, which respectively drive the first baffle (131) and the second baffle (132) to switch to rectangular surface, parallel side and radial tensioning form.

6. A double-arm drop test machine according to claim 1, characterized in that, It also includes a trigger rod (350) for driving the first clamping arm (341), the trigger rod (350) being rotatably disposed at the bottom of the ball seat (310); A main gear (360) is fixedly provided on the trigger rod (350), and a limiting plate (351) that can engage the second clamping arm (342) and the third clamping arm (343) is slidably provided on the second end of the trigger rod (350). A protrusion (352) is provided on the limiting plate (351). The annular track (330) is provided with a guide slope (331) for guiding the protrusion (352), and the limiting plate (351) is kept extended by a first elastic member (353); The ball seat (310) is also rotatably provided with a half gear (370) and a mating gear (380) at its bottom. The half gear (370) is fixedly connected to the third clamping arm (343), and the mating gear (380) can mesh with the main gear (360) and the half gear (370) respectively.

7. A double-arm drop test machine according to claim 6, characterized in that, The mating gear (380) includes a large gear at the upper end and a small gear at the lower end.

8. A double-arm drop test machine according to claim 6, characterized in that, The guide slope (331) is an arc-shaped protrusion extending circumferentially, and its starting end is offset from the protrusion (352) in the circumferential direction.

9. A double-arm drop test machine according to claim 6, characterized in that, The transmission ratio of the main gear (360) and the half gear (370) is 1:

3.

10. A double-arm drop test machine according to claim 1, characterized in that, The protective film (160) is made of polyurethane elastomer.

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