A drop weight impact testing machine

Abstract

The present invention belongs to the technical field of using mechanical stress to test the strength characteristics of solid materials, and specifically relates to a drop hammer impact testing machine, including a mounting frame, a guide tube, a holding mechanism located in the guide tube, and a drop hammer, the holding mechanism including an electromagnet, a mounting base, and a guide structure; the guide structure includes a claw mounting seat provided on the mounting base, at least three claws hinged on the claw mounting seat around a horizontal axis, and a claw driving component that drives each claw to swing synchronously, the electromagnet is located at the bottom of the claw mounting seat and is coaxially arranged with the claw mounting seat, the claws are evenly distributed on the claw mounting seat along the circumference of the claw mounting seat, and each claw includes a first arm located above the hinge axis and a second arm located below the hinge axis, the first arm is used to abut against the inner wall of the guide tube, and the second arm is used to abut against the drop hammer.

Description

Technical Field

[0001] The invention belongs to the technical field of testing the strength characteristics of solid materials by using mechanical stress, and particularly relates to a drop hammer impact testing machine. Background Art

[0002] In cable laying projects, cable protection tubes must have good impact resistance to ensure safe operation of cables. Drop hammer test is widely used as an important test method to detect the impact resistance of cable protection tubes, and drop hammer impact testing machine is the core equipment to realize this test method.

[0003] Existing drop-weight impact testing machines, such as those described in patent publication number CN222393919U, disclose a drop-weight impact testing device and apparatus for plastic pipes. The device comprises a base, a guide component, and a testing mechanism. The guide component comprises a guide tube, and the testing mechanism comprises a test bench component, an impact component, and a drive component. The test bench component is mounted on the base and corresponds to the guide tube. The impact component comprises a release electromagnet assembly and an impact head assembly. The drive component comprises a pulley assembly, a traction rope, and a drive member. The traction rope is connected to the electromagnet assembly, and the impact head assembly is attached to the electromagnet assembly. The drive member is connected to the traction rope, driving the electromagnet assembly and the impact head assembly to rise and fall within the guide tube.

[0004] During use, a plastic pipe is placed on the test bench. The electromagnet assembly is powered on to attract the impact head assembly. The traction rope drives the electromagnet assembly and the impact head assembly to a set height (for example, 1.2m). The electromagnet assembly is then powered off, and the impact head assembly drops alone, impacting the plastic pipe. The electromagnet assembly then descends to re-attract the impact head assembly, and after rising to the set height again, the impact head assembly drops alone again. This process is repeated multiple times.

[0005] Ideally, the axis of the impact head assembly is located at the center of the guide tube, and the impact head assembly falls vertically downward along the centerline of the guide tube, ensuring that the position of the impact head assembly remains consistent throughout multiple tests. This allows for multiple impacts on designated locations on the plastic pipe, thereby testing its impact resistance. However, in actual use, it has been found that the initial position of the impact head assembly at high altitude often deviates from the center axis of the guide tube and is relatively random. This is due to the following reasons: firstly, the electromagnet assembly is suspended by a traction rope, and the inherent defects of the traction rope suspension structure (such as the traction rope being a flexible element that is prone to elastic deformation and swinging when bearing weight) cannot ensure that the electromagnet assembly is located at the center of the guide tube; secondly, even if the electromagnet assembly is located at the center of the guide tube, the bottom of some electromagnet assemblies is flat (as in the aforementioned patent). When placing the impact head assembly, it is difficult to visually determine whether the impact head assembly and the electromagnet assembly are aligned.

[0006] When the initial position of the impact head assembly is not at the center of the guide tube, the landing point will be inconsistent during multiple tests. Moreover, since the initial position of the impact head assembly deviates from the central axis of the guide tube, it is easy for it to swing laterally during the falling process due to uneven pressure on the windward surface, eddy current effects, etc., which aggravates the randomness of the landing point and may even rub against the inner wall of the guide tube due to excessive deflection, affecting the test results and resulting in lower accuracy of the test results. Summary of the Invention

[0007] The present invention provides a drop hammer impact testing machine to solve the technical problem in the prior art that the electromagnet assembly and the impact head assembly are not located at the center of a guide tube, resulting in poor accuracy of the test results.

[0008] To solve the above-mentioned problems, the present invention provides a drop hammer impact testing machine that adopts the following technical solution: a drop hammer impact testing machine comprising a mounting frame, a guide tube mounted on the mounting frame, a lifting and lowering holding mechanism located in the guide tube, and a drop hammer, wherein the holding mechanism comprises an electromagnet for attracting the drop hammer; the holding mechanism comprises a mounting base, a guiding structure mounted on the mounting base, the guiding structure being used to guide the drop hammer to the center of the guide tube, and a traction rope being connected to the mounting base;

[0009] The guide structure includes a claw mounting base provided on a mounting base, at least three claws hinged to the claw mounting base around a horizontal axis, and a claw driving component for driving the claws to swing synchronously. The electromagnet is located at the bottom of the claw mounting base and is coaxially arranged with the claw mounting base. The claws are evenly distributed on the claw mounting base along the circumference of the claw mounting base. Each claw includes a first arm located above the hinge axis and a second arm located below the hinge axis. The first arm is used to abut against the inner wall of the guide tube, and the second arm is used to abut against the drop hammer.

[0010] The guiding structure has a guiding state and a disengaged state. When in the guiding state, each claw swings synchronously so that each first arm abuts against the inner wall of the guide tube and each second arm pushes and clamps the drop hammer; when in the disengaged state, each claw swings synchronously so that the second arm is separated from the drop hammer.

[0011] At least three claws swing synchronously. If the claw mounting base is not in the center of the guide tube, the first arm of each claw contacts and pushes against the inner wall of the guide tube in turn, guiding the position of the claw mounting base so that the claw mounting base is in the center of the guide tube. Since the claw mounting base and the electromagnet are coaxially arranged, it is guaranteed that the electromagnet is also in the center of the guide tube. If the drop hammer is not in the center of the guide tube, the second arm of each claw contacts and pushes against the drop hammer in turn, guiding the position of the drop hammer, and pushing the drop hammer horizontally on the electromagnet so that the drop hammer is in the center of the guide tube. In other words, the synchronous swinging of at least three claws ensures that the electromagnet and the drop hammer are coaxially arranged and located in the center of the guide tube, ensuring that the drop hammer will not produce lateral swing due to uneven windward surface, eddy current effect, etc. after being released, ensuring that the drop hammer drops to the same point during multiple tests, thereby improving the accuracy of the test results.

[0012] As a further improvement, the claw driving component includes a push ring, an electric cylinder driving the push ring to move up and down, and an elastic reset member;

[0013] The electric cylinder is fixed on the mounting base, and the pushing ring is located on the inner side of each claw and is used to push the inner side of the first arm downward;

[0014] The elastic reset member is used to apply elastic force to the push rod, so that the first arm swings toward the center of the guide tube and the second arm swings toward the inner wall of the guide tube.

[0015] As a further improvement, the claw mounting seat includes a mounting ring, and the claw is hinged on the mounting ring;

[0016] The electromagnet is fixed on the end of the electric cylinder, the push ring is located above the electromagnet, and the electric cylinder is used to push the electromagnet into the mounting ring.

[0017] As a further improvement, the bottom of the mounting ring is provided with a drop weight receiving groove coaxially arranged with the mounting ring;

[0018] The drop hammer comprises a magnetic chuck at the top, a hammer head at the bottom and a connecting rod connecting the magnetic chuck and the hammer head. The magnetic chuck is placed in the drop hammer receiving groove, and each second arm is used for clamping the connecting rod of the drop hammer together.

[0019] In actual use, the drop weight receiving slot is usually slightly larger than the magnetic chuck to facilitate its placement. The drop weight receiving slot accommodates the magnetic chuck and provides initial positioning for the drop weight. The second arm, which has at least three claws, then provides final positioning for the drop weight, making installation easy.

[0020] As a further improvement, the claw mounting seat is rotatably assembled on the mounting base around an axis extending up and down;

[0021] The drop weight impact tester further includes a cleaning structure, the cleaning structure including a brush disposed on the outer side of the second arm, and when the guide structure is in a disengaged state, the second arm swings toward the inner wall of the guide tube and causes the brush to adhere to the inner wall of the guide tube;

[0022] The cleaning structure also includes a rotary module for driving the claw mounting seat to rotate.

[0023] When the rotary module rotates the jaw mount, it also rotates the second arm, which then uses a brush to clean the inner wall of the guide tube. The second arm not only guides the falling hammer but also serves as a carrier for the brush, cleaning the inner wall of the guide tube. This centralized function reduces component count and reduces costs.

[0024] As a further improvement, the rotary module includes a rotating drum installed on a mounting base and rotating around an axis extending up and down. The rotating drum is sleeved on the outside of the claw mounting seat. The rotating drum is provided with an avoidance groove for avoiding the claw. The claw mounting seat is provided with a stop block located in the avoidance groove. When the rotating drum rotates, the groove wall of the avoidance groove pushes the stop block to drive the claw mounting seat to rotate.

[0025] As a further improvement, the bottom of the claw mounting base is provided with a cleaning strip receiving groove offset to one side, the cleaning structure further comprises a cleaning strip hinged in the cleaning strip receiving groove around an axis extending up and down, and the bottom of the rotating drum is provided with a clamping groove;

[0026] The cleaning strip includes a force-bearing part and a cleaning part, which are arranged on both sides of the horizontal axis of the cleaning strip hinge axis. The force-bearing part is located in the card slot of the rotating drum. The rotating drum is used to push the force-bearing part forward through the card slot to swing the cleaning part to the bottom of the electromagnet, and is also used to push the force-bearing part backward through the card slot to swing the cleaning part into the cleaning strip accommodating groove.

[0027] The cleaning strip can drive the rotating drum to swing, so that the cleaning part swings to the bottom of the electromagnet. After that, the cleaning strip rotates with the rotating drum, while the electromagnet does not rotate, so that the cleaning strip can clean the bottom surface of the electromagnet.

[0028] As a further improvement, the rotary module includes a drum driving component for driving the drum to rotate. The drum driving component includes a ring gear fixed on the inner wall of the top of the drum, an intermediate gear and a driving gear rotatably installed on the mounting base, and also includes a driving motor fixed on the mounting base, and the driving motor is connected to the driving gear.

[0029] As a further improvement, the installation base includes a top plate, a bottom plate and a connecting plate connecting the top plate and the bottom plate. The claw mounting seat is rotatably mounted on the bottom plate, and the rotating drum and the driving motor are both mounted on the top plate.

[0030] As a further improvement, the bottom of the second arm is an inclined surface, and when the guiding structure is in the guiding state, the inclined surface of the second arm is in contact with the drop weight.

[0031] The bottom of the second arm is an inclined surface. When the guide structure is in the guiding state, the second arm can fit on the drop weight. When the guide structure is in the disengaged state, the second arm is in a vertical state. After a single test, the drop weight is located in the guide tube and is tilted as a whole. The top of the drop weight abuts against the inner wall of the guide tube. After the second arm moves downward, the inclined surface of the second arm can push the top of the drop weight toward the center of the guide tube. When each second arm swings toward the center of the guide tube, the drop weight is re-guided to the center position of the guide tube, making it easier for the electromagnet to re-attract the drop weight for the next test, eliminating the need for manual removal and re-installation.

[0032] As a further improvement, the drop hammer includes a magnetic suction cup at the top, a hammer head at the bottom, and a connecting rod connecting the magnetic suction cup and the hammer head, and the second arm is used for clamping the connecting rod.

[0033] Beneficial effects:

[0034] 1. At least three claws swing synchronously. If the claw mounting seat is not in the center of the guide tube, the first arm of each claw contacts and pushes against the inner wall of the guide tube in turn, guiding the position of the claw mounting seat so that the claw mounting seat is in the center of the guide tube. Since the claw mounting seat and the electromagnet are coaxially arranged, it is guaranteed that the electromagnet is also in the center of the guide tube. If the drop hammer is not in the center of the guide tube, the second arm of each claw contacts and pushes against the drop hammer in turn, guiding the position of the drop hammer, and pushing the drop hammer horizontally on the electromagnet so that the drop hammer is in the center of the guide tube. In other words, the synchronous swinging of at least three claws ensures that the electromagnet and the drop hammer are coaxially arranged and located in the center of the guide tube, ensuring that the drop hammer will not swing horizontally after being released due to uneven windward surface, eddy current effect, etc., ensuring that the drop hammer drops to the same point during multiple tests, and improving the accuracy of the test results.

[0035] 2. In actual use, the drop weight receiving slot is usually slightly larger than the magnetic chuck to facilitate the placement of the magnetic chuck. The drop weight receiving slot accommodates the magnetic chuck and can provide initial positioning for the drop weight. The second arm with at least three claws then provides final positioning for the drop weight, making installation easy.

[0036] 3. When the rotary module drives the claw mounting base to rotate, it also drives the second arm to rotate. The brush on the second arm can clean the inner wall of the guide tube. The second arm not only guides the falling hammer, but also serves as a carrier for the brush, cleaning the inner wall of the guide tube. This centralized function reduces the number of parts and reduces costs.

[0037] 4. The cleaning strip can drive the rotating drum to swing, so that the cleaning part swings to the bottom of the electromagnet. After that, the cleaning strip rotates with the rotating drum, while the electromagnet does not rotate, so that the cleaning strip can clean the bottom surface of the electromagnet.

[0038] 5. The bottom of the second arm is an inclined surface. When the guide structure is in the guiding state, the second arm can fit on the drop weight. When the guide structure is in the disengaged state, the second arm is in a vertical state. After a single test, the drop weight is located in the guide tube and is tilted as a whole. The top of the drop weight abuts against the inner wall of the guide tube. After the second arm moves downward, the inclined surface of the second arm can push the top of the drop weight toward the center of the guide tube. When each second arm swings toward the center of the guide tube, the drop weight is re-guided to the center position of the guide tube, making it easier for the electromagnet to re-attract the drop weight for the next test, without the need for manual removal and re-installation. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is the main view of the drop weight impact testing machine;

[0040] Figure 2 It is the left view of the drop weight impact testing machine;

[0041] Figure 3 It is a top view of the drop weight impact testing machine;

[0042] Figure 4 for Figure 3 Cross-sectional view of section AA;

[0043] Figure 5 for Figure 4 Enlarged view of point A in the middle;

[0044] Figure 6 It is a structural diagram of the mounting frame, supporting mechanism and blocking mechanism assembled together;

[0045] Figure 7 Schematic diagram of the structure of the guide tube;

[0046] Figure 8 Schematic diagram of the structure of the drop hammer;

[0047] Figure 9 It is a structural diagram of the combination of the holding mechanism and the drop hammer when the three claws clamp the drop hammer;

[0048] Figure 10 Schematic diagram of the structure of the holding mechanism when the cleaning strip cleans the electromagnet (the brush is not shown in the figure);

[0049] Figure 11 Schematic diagram of the structure of the drop weight impact tester for cleaning the guide tube;

[0050] Figure 12 Structural diagram of the installation foundation;

[0051] Figure 13 This is a perspective view of the jaw mounting base;

[0052] Figure 14 This is a bottom view of the jaw mounting base;

[0053] Figure 15 A three-dimensional diagram of the rotating drum, water distribution block, and gear ring assembled together;

[0054] Figure 16 This is a structural diagram of the claws and elastic reset parts assembled together.

[0055] Description of reference numerals:

[0056] 1. Mounting frame; 11. Box body; 12. Box door; 13. Perforation;

[0057] 21. Support platform; 22. V-shaped placement groove; 23. First screw; 24. Second screw; 25. Pulley; 26. Synchronous belt; 27. Tensioner; 28. Handwheel;

[0058] 3. Guide tube; 31. Ring base; 32. Tube body; 33. Access door; 34. Side hole;

[0059] 4. Drop hammer; 41. Hammer head; 42. Connecting rod; 43. Magnetic chuck;

[0060] 51. Mounting base; 52. Electromagnet; 53. Top plate; 54. Bottom plate; 55. Connecting plate; 56. Connecting cylinder; 57. Clamping claw; 58. Mounting ring; 59. Connecting piece; 510. Articulated seat; 511. Drop hammer receiving groove; 512. Cleaning strip receiving groove; 513. Stop block; 514. First annular protrusion; 515. First groove; 516. First support arm; 517. Second support arm; 518. Electric cylinder; 519 , push ring; 520, elastic return member; 521, brush; 522, cleaning strip; 523, water distribution block; 524, rotating drum; 525, second annular protrusion; 526, second annular groove; 527, avoidance groove; 528, clamping groove; 529, driving motor; 530, ring gear; 531, intermediate gear; 532, driving gear; 533, cleaning part; 534, force-bearing part; 535, water inlet pipe; 536, water outlet;

[0061] 61. Pillar; 62. Pull rope;

[0062] 71. Telescopic member; 72. Stop block;

[0063] 8. Cable protection tube. DETAILED DESCRIPTION

[0064] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Those skilled in the art should know that the embodiments described below are part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present invention.

[0065] The embodiment of the drop weight impact testing machine provided by the present invention is as follows:

[0066] like Figures 1 to 16 As shown, the drop weight impact testing machine includes a mounting frame 1, a supporting mechanism, a guide tube 3, a drop weight 4, a holding mechanism, a driving mechanism, and a blocking mechanism. The supporting mechanism, the guide tube 3, the driving mechanism, and the blocking mechanism are all mounted on the mounting frame 1.

[0067] like Figure 1 and Figure 6 As shown, the mounting frame 1 includes a box body 11 and a box door 12. The front side opening of the box body 11 is used to place the cable protection tube 8 to be tested. The top of the box body 11 is provided with a through hole 13 that passes through from top to bottom. The box door 12 is installed at the front side opening of the box body 11 and is used to open and close the front side opening of the box body 11.

[0068] like Figure 6 As shown, the support mechanism, which supports the cable protection tube 8 under test, includes a support platform 21 and an adjustment structure. The support platform 21 is located within the housing 11. A V-shaped placement groove 22 is defined on the top surface of the support platform 21. The V-shaped placement groove 22 extends forward and backward. During testing, the cable protection tube 8 under test is placed in the V-shaped placement groove 22 with its axis extending forward and backward.

[0069] The function of the adjustment structure is to adjust the height of the support platform 21 , and the adjustment structure includes a first screw 23 , a second screw 24 , a pulley 25 , a synchronous belt 26 , a tensioning wheel 27 , and a hand wheel 28 .

[0070] The first and second screws 23, 24 are spaced apart and symmetrically arranged on either side of the through-hole 13. The first and second screws 23, 24 are rotatably mounted on the top and bottom of the housing 11 about vertically extending axes. The upper end of the second screw 14 extends upward from the housing 11, and a handwheel 28 is fixedly mounted on the upper end of the second screw 24.

[0071] The first screw rod 23 and the second screw rod 24 respectively pass through the support platform 21 and are threadedly engaged with the support platform 21. When the first screw rod 23 and the second screw rod 24 rotate in the same direction, they can drive the support platform 21 to move up and down.

[0072] Pulleys 25 are fixedly mounted at the bottom of each of the first and second screws 23 and 24. A tensioning pulley 27 is rotatably mounted at the bottom of the housing 11. A timing belt 26 is wound around the pulleys 25 and tensioning pulley 27 on the first and second screws 23 and 24. When the second screw 24 rotates, the timing belt 26 drives the first screw 23 to rotate synchronously in the same direction.

[0073] like Figures 1 to 5 as well as Figure 6 、 Figure 7 As shown, the guide tube 3 is fixedly mounted on the housing 11, extending vertically and aligning vertically with the through-hole 13 in the housing 11. The guide tube 3 comprises an annular base 31, a tube body 32, and a retrieval door 33. The annular base 31 is fixedly mounted on the housing 11, and a side hole 34 is defined on the left side of the annular base 31. The tube body 32 is secured to the annular base 31. Specifically, the tube body 32 can be placed into the annular base 31, with a threaded blind hole defined on the outer wall of the tube body 32. Bolts can pass through the annular base 31 and screw into the threaded blind hole in the tube body 32. Alternatively, the tube body 32 can be directly welded to the annular base 31. The front bottom of the tube body 32 is provided with an opening.

[0074] The access door 33 is a flat door hinged at the opening on the front side of the tube body 32. When the access door 33 is opened, the drop hammer 4 can be put into the tube body 32 and the drop hammer 4 can be taken out. The access door 33 needs to be closed during testing.

[0075] like Figure 8 As shown, the structure of the drop hammer 4 is conventional, comprising a hammer head 41, a connecting rod 42, and a magnetic chuck 43. The connecting rod 42 is fixed to the hammer head 41, and the magnetic chuck 43 is fixed to the connecting rod 42. The magnetic chuck 43 is connected to the holding mechanism, and the hammer head 41 is used to directly impact the cable protection tube 8 under test. The drop hammer 4 is a rotating body with a central axis.

[0076] like Figures 1 to 5 as well as Figures 9 to 16 As shown, the holding mechanism is connected to the drop hammer 4, driving it upward and then releasing it. The holding mechanism includes a mounting base 51, an electromagnet 52, a guide structure, and a cleaning structure. The mounting base 51 is connected to the drive mechanism, and the electromagnet 52 is used to attract the drop hammer 4.

[0077] The mounting base 51 includes a top plate 53, a bottom plate 54, a connecting plate 55, and a connecting tube 56. Both the top plate 53 and the bottom plate 54 are circular plates. The bottom plate 54 is located below the top plate 53 and has a smaller outer diameter than the top plate 53. The bottom plate 54 is secured to the top plate 53 via the connecting plates 55. Specifically, there are two connecting plates 55 arranged horizontally, with the tops of the two connecting plates 55 connected to the top plate 53 and the bottoms of the two connecting plates 55 connected to the bottom plate 54.

[0078] The connecting tube 56 is fixed on the top plate 53 . Specifically, the connecting tube 56 is buckled on the top plate 53 . The connecting tube 56 is used to be connected to the driving mechanism.

[0079] The guiding structure corrects the position of the drop weight 4, ensuring that its initial position is centered within the guide tube 3. The guiding structure includes a claw mounting base, a claw 57, and a claw drive assembly. The claw mounting base is mounted on the base plate 54, and the claw 57 is mounted on the claw mounting base.

[0080] The claw mounting base includes a mounting ring 58, a connecting piece 59, and a hinged base 510. The mounting ring 58 is located below the base plate 54 and is coaxially arranged with the base plate 54. The mounting ring 58 is mounted to the bottom of the base plate 54 via the connecting piece 59. The bottom of the mounting ring 58 is provided with a drop hammer accommodating groove 511 and a cleaning strip accommodating groove 512. The drop hammer accommodating groove 511 is located at the bottom center of the mounting ring 58 and is used to accommodate the magnetic suction cup 43 of the drop hammer 4. The cleaning strip accommodating groove 512 is located on one side of the bottom of the mounting ring 58 and is connected to the drop hammer accommodating groove 511. A stop block 513 is also fixedly mounted on the mounting ring 58.

[0081] The connecting piece 59 is an arc-shaped sheet structure. There are three connecting pieces 59, and the three connecting pieces 59 are located within the circumference of the same circle. The upper end of the connecting piece 59 is mounted on the base plate 54, and the lower end is connected to the mounting ring 58. Specifically, the lower end of the connecting piece 59 can be welded to the mounting ring 58. Here, a first annular protrusion 514 is formed on the outer edge of the base plate 54, and a first groove 515 is formed on the inner side of the top of each connecting piece 59. The first annular protrusion 514 is adaptively snapped into the first groove 515. Through the cooperation of the first annular protrusion 514 and the first groove 515, the connecting piece 59 and the base plate 54 can be relatively fixed in the vertical direction and can rotate relative to each other in the circumferential direction.

[0082] The hinge seats 510 are mounted on the mounting ring 58 . There are three hinge seats 510 . The three hinge seats 510 and the three connecting pieces 59 are alternately arranged in the circumferential direction.

[0083] The claw 57 is hinged about a horizontal axis on the claw mounting base. Specifically, the claw 57 is mounted on the hinge base 510, and the claw 57 can swing up and down. The claw 57 includes a first arm 516 and a second arm 517. Here, the first arm 516 and the second arm 517 are of an integrated structure. The second arm 517 is L-shaped, and the angle formed between the second arm 517 and the first arm 516 is an acute angle. The intersection of the first arm 516 and the second arm 517 is mounted on the hinge base 510. The first arm 516 is located above the hinge axis, and the second arm 517 is located below the hinge axis.

[0084] The end of the first arm 516 is used to support the inner wall of the guide tube 3, and the end of the second arm 517 is used to support the connecting rod 42 of the drop hammer 4, wherein the end of the second arm 517 is an inclined surface, and when the second arm 517 swings toward the connecting rod 42, the end of the second arm 517 is in contact with the connecting rod 42.

[0085] The claw drive assembly, which drives the claw 57 to swing up and down, includes an electric cylinder 518, a push ring 519, and an elastic return member 520. The cylinder body of the electric cylinder 518 is fixedly mounted on the top of the base plate 54, with a gap between the top of the electric cylinder 518 and the top plate 53. The piston rod of the electric cylinder 518 extends downward to the bottom of the base plate 54.

[0086] The push ring 519 is fixedly mounted on the piston rod of the electric cylinder 518 . The push ring 519 is located on the inner sides of the three first arms 516 . When the push ring 519 moves downward, it can push the inner sides of the three first arms 516 at the same time.

[0087] It should be noted that the “inner side” here refers to the side facing the central axis of the guide tube 3 , and the “outer side” refers to the side facing the inner wall of the guide tube 3 .

[0088] The electromagnet 52 is fixedly mounted at the bottom of the piston rod of the electric cylinder 518, with a push ring 519 positioned above the electromagnet 52. The electromagnet 52 is coaxially arranged with the claw mounting base. The electric cylinder 518 is capable of pushing the electromagnet 52 into the interior of the mounting ring 58. When the second arm 517 presses against the connecting rod 42, the bottom of the electromagnet 52 extends into the interior of the drop hammer receiving groove 511, or the bottom surface of the electromagnet 52 is flush with the top surface of the drop hammer receiving groove 511, allowing the electromagnet 52 to attract the magnetic suction cup 43 of the drop hammer 4.

[0089] The effect of elastic reset member 520 is to drive claw 57 to reset, so that the first arm 516 of claw 57 is swung inwards and the second arm 517 of claw 57 is swung outwards. The elastic reset member 520 here is a torsion spring, which is installed between claw 57 and hinge seat 510.

[0090] In this embodiment, the end of the first arm 516 is made of rubber, which can avoid rigid collision and friction with the inner wall of the guide tube 3 and protect the inner wall of the guide tube 3.

[0091] The cleaning structure cleans the inner wall of the guide tube 3 and the bottom of the electromagnet 52. After prolonged use, dust and other impurities may accumulate on the inner wall of the guide tube 3 and the bottom of the electromagnet 52. The cleaning structure includes a brush 521, a cleaning strip 522, a rotary module, and a water diversion block 523. The brush 521 is fixedly mounted on the outside of the second arm 517. When the elastic return member drives the second arm 517 to swing outward, the brush 521 presses against the inner wall of the guide tube 3.

[0092] The function of the rotary module is to drive the claw 57 to rotate. The rotary module includes a drum 524 and a drum driving component. The drum 524 is sleeved on the outside of the top plate 53. Specifically, the top and bottom of the drum 524 are open. A second annular protrusion 525 is formed on the top outer side of the top plate 53. A second annular groove 526 is formed on the top inner side of the drum 524. The second annular protrusion 525 extends into the second annular groove 526, so that the drum 524 and the top plate 53 are relatively fixed in the vertical direction and can rotate relative to each other in the circumferential direction. In order to allow the second annular protrusion 525 to extend into the second annular groove 526, the drum 524 can be designed as a split structure. The drum 524 is divided into two parts by a vertical plane. The two parts are both fastened to the second annular protrusion 525 and then assembled together. The specific assembly method can be welding, or ear plates are provided on both parts and connected with bolts.

[0093] The bottom of the rotating drum 524 is provided with a clearance groove 527 corresponding to each claw 57, which allows the claw 57 to extend outward. The bottom of the rotating drum 524 is also provided with a clamping groove 528, which allows the cleaning strip 522 to extend into. The stop block 513 on the mounting ring 58 is located in the clearance groove 527 of the rotating drum 524.

[0094] The function of the drum drive assembly is to drive the drum 524 to rotate. The drum drive assembly includes a drive motor 529, a ring gear 530, an intermediate gear 531, and a drive gear 532. The drive motor 529 is fixedly mounted on the top of the top plate 53 and is located in the connecting tube 56. The ring gear 530 is fixedly mounted on the top inner wall of the drum 524 and is located below the top plate 53. The ring gear 530 has meshing teeth. The intermediate gear 531 is rotatably mounted below the top plate 53 about an axis extending vertically. The intermediate gear 531 meshes with the ring gear 530. The output shaft of the drive motor 529 passes downwardly below the top plate 53. The drive gear 532 is fixedly mounted on the output shaft of the drive motor 529 and meshes with the intermediate gear 531. After the driving motor 529 is started, it drives the driving gear 532 to rotate, the driving gear 532 drives the intermediate gear 531 to rotate, the intermediate gear 531 drives the ring gear 530 to rotate, and the ring gear 530 drives the rotating drum 524 to rotate.

[0095] The cleaning strip 522 is rotatably mounted on the bottom of the mounting ring 58 about an axis extending vertically. Specifically, the cleaning strip 522 includes a cleaning portion 533 and a force-bearing portion 534 arranged at an angle. The intersection of the cleaning portion 533 and the force-bearing portion 534 is rotatably mounted in the cleaning strip receiving slot 512 of the mounting ring 58. The force-bearing portion 534 is located in the retaining slot 528 of the rotating drum 524. The cleaning portion 533 has an arc-shaped structure and can be received in the cleaning strip receiving slot 512 or swung below the electromagnet 52. A cleaning layer such as cotton cloth can be placed on top of the cleaning portion 533.

[0096] The water diversion block 523 is fixedly mounted on the outside of the rotating drum 524, above the claws 57. The water diversion block 523 has a chamber inside, and a water inlet pipe 535 is fixedly mounted on the top of the water diversion block 523. The water inlet pipe 535 is used to pass water or other cleaning liquid into the water diversion block 523. The water diversion block 523 is provided with multiple water outlets 536 on the outside, which are used to spray water or cleaning liquid onto the inner wall of the guide tube 3.

[0097] The driving mechanism drives the holding mechanism to move up and down. The driving mechanism includes a column 61 and a pulling rope 62. The column 61 is fixedly mounted on the mounting frame 1, extending vertically and located on the horizontal side of the guide tube 3. The pulling rope 62 is connected to the connecting tube 56 of the holding mechanism. The driving mechanism also includes a structure mounted on the top of the column 61 to drive the pulling rope 62 up and down. This structure is conventional, and can be equipped with a winch or other structure, so it will not be described in detail here.

[0098] like Figures 1 to 7 As shown, the function of the blocking mechanism is to prevent the falling hammer 4 from repeatedly impacting the cable protection tube 8 to be tested. After the falling hammer 4 falls and impacts the cable protection tube 8 to be tested for the first time, it will bounce upwards, and then fall downwards under its own weight, which will produce a second or more impact on the cable protection tube 8. In order to avoid such a situation, a blocking mechanism is provided. The blocking mechanism includes a telescopic member 71 and a blocking block 72. The telescopic member 71 is fixedly mounted on the top of the mounting frame 1. The telescopic member 71 here can adopt one of an electric cylinder, a hydraulic cylinder, and an air cylinder. The output end of the telescopic member 71 is telescopic in the horizontal direction. The blocking block 72 is fixedly mounted on the output end of the telescopic member 71. The blocking block 72 is opposite to the side hole 34 on the annular base 31. The telescopic member 71 can drive the blocking block 72 through the side hole 34 and extend into the interior of the guide tube 3, and can also pull the blocking block 72 out of the guide tube 3.

[0099] Usage: In the initial state, the drive mechanism lowers the holding mechanism to the position of the access door 33. The electric cylinder 518 drives the push ring 519 and the electromagnet 52 upward, and the claws 57 swing under the action of the elastic return member 520. The second arm 517 of each claw 57 swings toward the inner wall of the guide tube 3. The access door 33 is opened, and the magnetic suction cup 43 of the drop hammer 4 is placed into the drop hammer receiving groove 511. The electric cylinder 518 drives the push ring 519 and the electromagnet 52 downward. The electromagnet 52 is energized to attract the drop hammer 4. At the same time, the second arm 517 of each claw 57 swings inward, and the first arm 516 swings outward.

[0100] During the synchronous swinging of the first and second arms 516, 517, if the claw mounting seat is not at the center of the guide tube 3, the first arms 516 will sequentially contact and abut the inner wall of the guide tube 3 to correct the position of the claw mounting seat. If the drop hammer 4 is not at the center of the claw mounting seat, the second arms 517 will sequentially contact and abut the drop hammer 4 to correct the position of the drop hammer 4. It should be noted that although the drop hammer 4 is adsorbed on the electromagnet 52, in the horizontal direction, the thrust of the second arm 517 on the drop hammer 4 can overcome the adsorption force of the electromagnet 52 on the drop hammer 4, causing the drop hammer 4 to move horizontally. At this time, the correction structure is in the correction state.

[0101] After aligning the claw mounting base and drop weight 4, the drive mechanism raises the retaining mechanism and drop weight 4 to a set height (e.g., 1.2 m). During this raising process, the second arm 517 clamps the drop weight 4, preventing it from falling even if the electromagnet 52 loses power due to a malfunction. The first arm 516 moves upward against the guide tube 3. It should be noted that, in actual use, a structure such as a ball bearing can be installed at the end of the first arm 516 to reduce friction between the first arm 516 and the guide tube 3.

[0102] After reaching the set height, the electromagnet 52 loses power. Simultaneously, the electric cylinder 518 drives the push ring 519 and the electromagnet 52 upward. The second arm 517, under the action of the elastic return member, swings toward the inner wall of the guide tube 3, quickly releasing the drop hammer 4, which strikes the cable protection tube 8 on the support platform 21. After the drop hammer 4 bounces upward, the telescopic member 71 drives the stop block 72 into the guide tube 3, and the drop hammer 4 finally lands on the stop block 72. The drop hammer 4 is arranged at an angle, with the top resting on the inner wall of the guide tube 3. At this point, the guide structure is in a disengaged state.

[0103] The drive mechanism then lowers the holding mechanism, and the vertical second arm 517, guided by the inclined surface at its end, is inserted beneath the magnetic cup 43. The electric cylinder 518 then drives the push ring 519 downward, causing each second arm 517 to swing inward, gradually straightening the drop hammer 4. Simultaneously, the electromagnet 52 moves downward and attracts the drop hammer 4. As the first and second arms 516, 517 swing, they align the claw mounting base and the drop hammer 4. After re-attracting the drop hammer 4, they are lifted up for the next test.

[0104] During use, dust within the guide tube 3 easily falls onto the inner wall of the guide tube 3 and the bottom surface of the electromagnet 52, necessitating cleaning. To clean the inner wall of the guide tube 3, the electric cylinder 518 drives the electromagnet 52 upward, causing the brush 521 to contact the inner wall of the guide tube 3. The drive motor 529 rotates the rotating drum 524, which pushes against the stop block 513, driving the claw mounting base to rotate. As the claw mounting base rotates, water or cleaning fluid is introduced into the water inlet pipe 535, spraying the water or cleaning fluid onto the inner wall of the guide tube 3.

[0105] When cleaning the bottom surface of the electromagnet 52, the electric cylinder 518 drives the electromagnet 52 to move downward. The drive motor 529 drives the rotating drum 524 to rotate. The rotating drum 524 pushes the cleaning bar 522 in the positive direction through the slot 528, causing the cleaning portion 533 to swing below the electromagnet 52. Subsequently, the rotating drum 524 pushes the stop block 513, driving the claw mounting base to rotate, while the electromagnet 52 does not rotate. The cleaning portion 533 rotates relative to the electromagnet 52 to clean the bottom surface of the electromagnet 52. After cleaning the bottom surface of the electromagnet 52, the rotating drum 524 pushes the cleaning bar 522 in the direction of the slot 528, causing the cleaning portion 533 to swing into the cleaning bar receiving slot 512. It should be noted that the terms "forward" and "reverse" are relative terms and do not limit the structure.

[0106] In this embodiment, the electromagnet 52 is fixedly mounted on the electric cylinder 518. In other embodiments, the electromagnet 52 is fixedly mounted on the claw mounting base, and the electromagnet 52 and the claw mounting base are arranged coaxially. In this case, after the drop hammer 4 is placed in the guide tube 3, the electromagnet 52 is energized to attract the drop hammer 4, but the second arm 517 does not clamp the drop hammer 4. After the drop hammer 4 is raised to the set height, the electric cylinder 518 drives the push ring 519 downward, driving the second arm 517 to swing inward and the first arm 516 to swing outward, thereby correcting the position of the drop hammer 4. This method can prevent friction between the first arm 516 and the inner wall of the guide tube 3 during the lifting process of the drop hammer 4.

[0107] In other embodiments, if only the inner wall of the guide tube 3 is to be cleaned, the cleaning strip 522 may be removed. In this case, the rotating drum 524 may be fixedly mounted together with the claw mounting base.

[0108] In other embodiments, if the purpose is only to guide the drop hammer 4, the cleaning structure can be completely eliminated.

[0109] In addition, in the description of this specification, “a plurality of” means at least two, for example, two, three or more, etc., unless otherwise clearly and specifically defined.

Claims

1. A drop hammer impact testing machine, comprising a mounting frame, a guide tube mounted on the mounting frame, a lifting and lowering holding mechanism located in the guide tube, and a drop hammer, wherein the holding mechanism comprises an electromagnet for attracting the drop hammer; characterized in that: The holding mechanism includes a mounting base and a guide structure provided on the mounting base, the guide structure is used to guide the drop hammer to the center of the guide tube, and a traction rope is connected to the mounting base; The guide structure includes a claw mounting base provided on a mounting base, at least three claws hinged to the claw mounting base around a horizontal axis, and a claw driving component for driving the claws to swing synchronously. The electromagnet is located at the bottom of the claw mounting base and is coaxially arranged with the claw mounting base. The claws are evenly distributed on the claw mounting base along the circumference of the claw mounting base. Each claw includes a first arm located above the hinge axis and a second arm located below the hinge axis. The first arm is used to abut against the inner wall of the guide tube, and the second arm is used to abut against the drop hammer. The guiding structure has a guiding state and a disengaged state. When in the guiding state, each claw swings synchronously so that each first arm abuts against the inner wall of the guide tube and each second arm pushes and clamps the drop hammer; when in the disengaged state, each claw swings synchronously so that the second arm is separated from the drop hammer.

2. The drop weight impact testing machine according to claim 1, characterized in that: The claw driving component includes a push ring, an electric cylinder that drives the push ring to move up and down, and an elastic reset member; The electric cylinder is fixed on the mounting base, and the pushing ring is located on the inner side of each claw and is used to push the inner side of the first arm downward; The elastic reset member is used to apply elastic force to the push rod, so that the first arm swings toward the center of the guide tube and the second arm swings toward the inner wall of the guide tube.

3. The drop weight impact testing machine according to claim 2, characterized in that: The claw mounting seat includes a mounting ring, and the claw is hinged on the mounting ring; The electromagnet is fixed on the end of the electric cylinder, the push ring is located above the electromagnet, and the electric cylinder is used to push the electromagnet into the mounting ring.

4. The drop weight impact testing machine according to claim 3, characterized in that: The bottom of the mounting ring is provided with a drop weight receiving groove coaxially arranged with the mounting ring; The drop hammer comprises a magnetic chuck at the top, a hammer head at the bottom and a connecting rod connecting the magnetic chuck and the hammer head. The magnetic chuck is placed in the drop hammer receiving groove, and each second arm is used for clamping the connecting rod of the drop hammer together.

5. The drop weight impact testing machine according to any one of claims 1 to 4, characterized in that: The claw mounting seat is rotatably assembled on the mounting base around an axis extending up and down; The drop weight impact tester further includes a cleaning structure, the cleaning structure including a brush disposed on the outer side of the second arm, and when the guide structure is in a disengaged state, the second arm swings toward the inner wall of the guide tube and causes the brush to adhere to the inner wall of the guide tube; The cleaning structure also includes a rotary module for driving the claw mounting seat to rotate.

6. The drop weight impact testing machine according to claim 5, characterized in that: The rotary module includes a rotating drum installed on a mounting base and rotating around an axis extending up and down. The rotating drum is sleeved on the outside of the claw mounting seat. The rotating drum is provided with an avoidance groove for avoiding the claw. The claw mounting seat is provided with a stop block located in the avoidance groove. When the rotating drum rotates, the groove wall of the avoidance groove pushes the stop block to drive the claw mounting seat to rotate.

7. The drop weight impact testing machine according to claim 6, characterized in that: The bottom of the claw mounting base is provided with a cleaning strip receiving groove offset to one side, the cleaning structure further comprises a cleaning strip hinged in the cleaning strip receiving groove around an axis extending up and down, and the bottom of the rotating drum is provided with a clamping groove; The cleaning strip includes a force-bearing part and a cleaning part, which are arranged on both sides of the horizontal axis of the cleaning strip hinge axis. The force-bearing part is located in the card slot of the rotating drum. The rotating drum is used to push the force-bearing part forward through the card slot to swing the cleaning part to the bottom of the electromagnet, and is also used to push the force-bearing part backward through the card slot to swing the cleaning part into the cleaning strip accommodating groove.

8. The drop weight impact testing machine according to claim 6, characterized in that: The rotary module includes a drum driving component that drives the drum to rotate. The drum driving component includes a ring gear fixed on the inner wall of the top of the drum, an intermediate gear and a driving gear rotatably installed on the mounting base, and also includes a driving motor fixed on the mounting base, and the driving motor is connected to the driving gear.

9. The drop weight impact testing machine according to claim 8, characterized in that: The installation base comprises a top plate, a bottom plate and a connecting plate connecting the top plate and the bottom plate; the clamping claw mounting seat is rotatably mounted on the bottom plate; and the rotating drum and the driving motor are both mounted on the top plate.

10. The drop weight impact testing machine according to any one of claims 1 to 4, characterized in that: The bottom of the second arm is an inclined surface. When the guiding structure is in the guiding state, the inclined surface of the second arm is in contact with the drop weight.

Images