Single-rod pull-down type half-sinusoidal waveform impact test bench

Abstract

The utility model provides a single-rod pull-down type half-sinusoidal waveform impact test bench, which comprises a base, an impact platform arranged above the base in a manner of moving up and down, a connecting rod inserted into the base in a manner of moving up and down, and a waveform pad sleeved on the connecting rod and positioned between the base and the impact platform, a sensor for detecting impact signals is arranged on the impact platform, the upper end of the connecting rod protrudes out of the upper end face of the base and is connected with the center of the bottom of the impact platform, the lower end of the connecting rod extends into the base and is connected with a driver for driving the connecting rod to move up and down, and the waveform pad is connected to the upper end face of the base. The wave-shaped pad is divided into at least two block-shaped pads in the radial direction of the connecting rod, the two block-shaped pads are symmetrically distributed on the two sides of the connecting rod and connected with the upper end face of the base, all block-shaped pads can be taken out from the side face and replaced, replacement of the whole wave-shaped pad is achieved, operation is easy and convenient, and time and labor are saved.

Description

Technical Field

[0001] The utility model belongs to the technical field of impact test equipment, and in particular relates to a single-rod pull-down type semi-sine waveform impact test bench. Background Art

[0002] The impact test bench is a device for impact testing. According to different structures, it can be roughly divided into free fall type and force-added type. The free fall type impact test bench only relies on the free fall of the object to be tested to achieve impact. The indicators that can be achieved in the impact test are low and the scope of application is limited. The force-added impact test bench not only uses the impact force of the object to be tested during free fall to achieve impact, but also pulls down the connecting rod at the bottom of the impact platform to add force. For example, Chinese patents CN2202084300U, CN205317439U, and CN211855774U disclose this type of impact test bench. The number of connecting rods is divided into single and multiple. The pulling down of the connecting rod can be achieved by compressed gas drive, electric drive, etc. If the output of a semi-sine waveform is to be achieved, a corrugated pad is also required to be arranged under the impact platform so that the impact platform can rebound with a gradually decreasing height after impact. For a pull-down impact test bench with multiple connecting rods, the corrugated pad can be arranged in the middle of the multiple connecting rods. When adjusting the indicators of the impact test, the impact platform is lifted up by the connecting rod, and the corrugated pad can be removed and replaced through the intervals between adjacent connecting rods, but the pull-down action of multiple connecting rods is difficult to be completely consistent, which will affect the accuracy of the test results to a certain extent; for the pull-down impact test bench with a single connecting rod, there is no problem of consistency in the pull-down action, but in order to ensure that the impact platform can fully contact the corrugated pad during impact, it is necessary to first open a through hole in the center of the corrugated pad for passing the connecting rod, and then the corrugated pad can be put on the connecting rod before it can be fixed under the impact platform. In this way, the corrugated pad cannot be removed directly from the side. When adjusting the indicators of the impact test, it is necessary to first disassemble the connection between the impact platform and the connecting rod, then remove the impact platform, and then remove the corrugated pad and replace it. After the replacement is completed, the impact platform needs to be reinstalled, which is inconvenient to operate, and the relative position of the impact platform and the connecting rod before and after the replacement of the corrugated pad is difficult to ensure consistency, which will affect the consistency of the test conditions. Utility Model Content

[0003] The utility model aims to overcome the shortcomings of the prior art and provide a single-rod pull-down type semi-sine waveform impact test bench with simple and convenient replacement of the waveform pad.

[0004] In order to achieve the above-mentioned purpose, the technical solution adopted by the utility model is a single-rod pull-down semi-sine waveform impact test bench, comprising:

[0005] Base;

[0006] An impact platform, the impact platform is movably disposed above the base, and a sensor for detecting an impact signal is disposed on the impact platform;

[0007] A connecting rod, the connecting rod is inserted into the base so as to be movable up and down, the upper end of the connecting rod protrudes from the upper end surface of the base and is connected to the bottom center of the impact platform, and the lower end of the connecting rod extends into the base and is connected to a driver for driving the connecting rod to move up and down;

[0008] A corrugated pad, wherein the corrugated pad is sleeved on the connecting rod and located between the base and the impact platform, and the corrugated pad is connected to the upper end surface of the base; the corrugated pad is divided into at least two block pads along the radial direction of the connecting rod, and the two block pads are distributed on both sides of the connecting rod and are respectively connected to the upper end surface of the base.

[0009] Preferably, when connected to the upper end surface of the base, the spacing between the facing side surfaces of adjacent block-shaped pads is less than or equal to 0.5 mm.

[0010] Preferably, the corrugated pad comprises a metal chassis and a polyurethane block or a rubber block molded on the metal chassis, a first through hole for the connecting rod to pass through is opened at the center of the metal chassis, a second through hole for the connecting rod to pass through is opened at the center of the polyurethane block or the rubber block, the second through hole is coaxial with the first through hole and has the same aperture.

[0011] Further preferably, the metal chassis is provided with bolt holes for connecting the base, and there are a plurality of the bolt holes distributed on the outside of the polyurethane block or the rubber block, and adjacent bolt holes are spaced apart.

[0012] Further preferably, the upper surface of the metal chassis is provided with a connecting structure for enhancing the connection force between the polyurethane block or the rubber block and the metal chassis, the connecting structure includes a connecting hole group and an annular connecting groove, the connecting hole group has multiple groups, each of the connecting hole groups includes a number of connecting holes evenly distributed around the axis of the first through hole, all of the connecting hole groups are distributed in concentric circles around the axis of the first through hole, the annular connecting groove is coaxially arranged on the outside of the first through hole, and the annular connecting groove has multiple paths and is distributed in concentric circles around the axis of the first through hole.

[0013] Further preferably, the annular connecting grooves and the connecting hole groups are arranged alternately, and the intervals between adjacent annular connecting grooves and the connecting hole groups are equal.

[0014] Further preferably, the connecting hole is a countersunk hole, the countersunk end of the connecting hole is located on the lower surface of the metal chassis, and the cross-section of the annular connecting groove is V-shaped.

[0015] Further preferably, the bottom of the polyurethane block or the rubber block is filled in all the annular connecting grooves and all the connecting holes.

[0016] Further preferably, the polyurethane block is formed by solidifying liquid polyurethane poured on the metal chassis, and the rubber block is formed by solidifying liquid rubber poured on the metal chassis.

[0017] Further preferably, the lower end of the polyurethane block or the rubber block is cylindrical, and the upper end is a truncated cone with a cone angle of 165-170°.

[0018] Due to the application of the above technical solution, the utility model has the following advantages compared with the prior art:

[0019] The utility model provides a single-rod pull-down type semi-sine waveform impact test bench, comprising a base, an impact platform movably arranged above the base, a connecting rod movably inserted in the base, and a corrugated pad sleeved on the connecting rod and located between the base and the impact platform; the impact platform is provided with a sensor for detecting an impact signal; the upper end of the connecting rod protrudes from the upper end surface of the base and is connected to the bottom center of the impact platform; the lower end of the connecting rod extends into the base and is connected to a driver for driving the connecting rod to move up and down; the corrugated pad is connected to the upper end surface of the base; the corrugated pad is divided into at least two block pads along the radial direction of the connecting rod, the two block pads are distributed on both sides of the connecting rod and are respectively connected to the upper end surface of the base; the entire corrugated pad can be replaced by taking out all the block pads from the side and replacing them; the operation is simple and convenient, and time and labor are saved. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a three-dimensional schematic diagram of a preferred embodiment of the utility model.

[0021] Figure 2 yes Figure 1 A local enlarged schematic diagram of point A in the middle.

[0022] Figure 3 yes Figure 1 Schematic diagram of the top view of the medium corrugated pad.

[0023] Figure 4 yes Figure 3 Schematic cross-sectional view along the BB direction.

[0024] Figure 5 yes Figure 4 A partial enlarged schematic diagram of point C in the middle.

[0025] Figure 6 yes Figure 1 Schematic diagram of top view of the corrugated pad before segmentation.

[0026] Figure 7 yes Figure 6 Schematic diagram of the main view.

[0027] Figure 8 Figure 6 Schematic diagram of the top view of the metal chassis.

[0028] Fig. 9 yes Figure 8 Schematic diagram from top view.

[0029] Fig.10 It is a top view schematic diagram of a metal chassis in another embodiment of the utility model.

[0030] Among them: 10. base; 20. impact platform; 30. connecting rod; 40. corrugated pad; 41. block pad; 42. metal chassis; 421. first through hole; 422. bolt hole; 423. connecting hole group; 424. annular connecting groove; 425. connecting hole; 43. polyurethane block; 431. second through hole. DETAILED DESCRIPTION

[0031] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0032] like Figures 1 to 9As shown, the single-rod pull-down semi-sine waveform impact test bench provided by the utility model includes: a base 10, an impact platform 20, a connecting rod 30, and a corrugated pad 40, wherein the impact platform 20 is movably arranged above the base 10, the upper surface of the impact platform 20 is used to place the object to be tested, and a sensor for detecting the impact signal (not shown in the figure) is provided on the impact platform 20; the connecting rod 30 is movably inserted into the base 10, the upper end of the connecting rod 30 protrudes from the upper end surface of the base 10 and is connected to the bottom center of the impact platform 20, the lower end of the connecting rod 30 extends into the base 10 and is connected to a driver for driving the connecting rod 30 to move up and down, the connecting rod 30 can be a cylinder rod, at this time, the driver is a cylinder body and a piston matched with the cylinder rod, and the connecting rod 30 is energized by compressed gas The rod 30 moves up and down, and the connecting rod 30 can also be an ordinary rod. In this case, the driver is a motor cam system or other electric starting system; the corrugated pad 40 is sleeved on the connecting rod 30 and is located between the base 10 and the impact platform 20. Specifically, the corrugated pad 40 is connected to the upper end surface of the base 10; the corrugated pad 40 is divided into two block pads 41 along the radial direction of the connecting rod 30, and the two block pads 41 are symmetrically distributed on both sides of the connecting rod 30 and are respectively connected to the upper end surface of the base 10, that is, the corrugated pad 40 includes two block pads 41, all the block pads 41 are symmetrically distributed around the connecting rod 30 and are respectively connected to the upper end surface of the base 10, together constituting a corrugated pad 40 sleeved on the connecting rod 30, and the surfaces of the facing sides of adjacent block pads 41 are in the same plane as the axial center line of the connecting rod 30.

[0033] The advantage of this arrangement is that when adjusting the impact test indicators, the entire corrugated pad can be replaced by taking out all the block pads from the side and replacing them, without disassembling the connecting part between the connecting rod and the impact platform. The operation is simple and convenient, saving time and effort.

[0034] In other embodiments, the corrugated pad 40 may also include three or more block pads 41 , and all the block pads 41 are evenly distributed around the axis of the connecting rod 30 .

[0035] In this embodiment, the corrugated pad 40 is first processed and formed in an integral form, and then cut into at least two block pads 41 by a cutting device. During cutting, the slit width is controlled at 0.3-0.5 mm. When connected to the upper end surface of the base, the spacing between the facing side surfaces of adjacent block pads 41 is less than or equal to 0.5 mm. When under pressure, the spacing can accommodate the deformation of the facing side surfaces of adjacent block pads 41.

[0036] In this embodiment, the corrugated pad 40 includes a metal chassis 42 and a polyurethane block 43 formed on the metal chassis 42. A first through hole 421 for the connecting rod 30 to pass through is opened at the center of the metal chassis 42. A second through hole 431 for the connecting rod 30 to pass through is opened at the center of the polyurethane block 43. The second through hole 431 is coaxial with the first through hole 421 and has the same aperture diameter (the aperture diameter is larger than the diameter of the connecting rod 30).

[0037] In order to facilitate connection with the base 10 , the metal chassis 42 is further provided with bolt holes 422 for connecting with the base 10 . There are a plurality of bolt holes 422 distributed on the outside of the polyurethane block 43 , and adjacent bolt holes 422 are spaced apart.

[0038] At the same time, in order to enhance the connection force of the polyurethane block 43, the upper surface of the metal chassis 42 is also provided with a connection structure for enhancing the connection force between the polyurethane block 43 and the metal chassis 41, and the connection structure includes a connection hole group 423 and an annular connection groove 424. There are multiple groups of connection hole groups 423, and each group of connection hole groups 423 includes a plurality of connection holes 425 uniformly distributed around the axis of the first through hole 421. All the connection hole groups 423 are distributed in concentric circles around the axis of the first through hole 421, and there is no deflection between adjacent connection hole groups 423. In another embodiment, as Fig.10 As shown, adjacent connection hole groups 423 are deflected so that there is at most one connection hole 425 on any radius of the metal chassis 42; the annular connection groove 424 is coaxially arranged on the outside of the first through hole 421, and the annular connection groove 424 has multiple channels and is distributed in concentric circles around the axis of the first through hole 421; further, the annular connection grooves 424 and the connection hole groups 423 are staggered, and the spacing between adjacent annular connection grooves 424 and the connection hole groups 423 is equal; further, the connection hole 425 is a countersunk hole, and the countersunk end of the connection hole 425 is located on the lower surface of the metal chassis 42, and the cross-section of the annular connection groove 424 is V-shaped, and the bottom of the polyurethane block 43 is filled in all the annular connection grooves 424 and all the connection holes 425. For the convenience of filling, further, the polyurethane block 43 is formed by curing liquid polyurethane cast on the metal chassis 42, and a mold is required for matching during casting.

[0039] In order to better realize the rebound required by the half-sine wave, in the present embodiment, the lower end of the polyurethane block 43 is cylindrical, and the upper end is a truncated cone with a cone angle of 165-170°.

[0040] In another embodiment of the utility model, the impact test bench is a single-cylinder impact test bench with a relatively small table top and a piston rod in the center of the table top. The prior art usually uses a ring-shaped wool felt with a hole in the middle under the table top, which is sleeved on the piston rod as a waveform generator. After the wool felt is impacted by the table top, a semi-sine waveform will be generated on the table top. Due to the characteristics of the wool felt, it will be deformed after the impact, and the thickness will become thinner with each collision, so that the peak acceleration value of the semi-sine wave generated on the table top after the impact becomes larger and larger, while the duration of the impact pulse becomes smaller and smaller, resulting in poor repeatability of the impact.

[0041] In this embodiment, the corrugated pad structure in the aforementioned embodiment is adopted, and polyurethane or rubber material is used as the impact-resistant block on the metal chassis. When the rubber or polyurethane material is impacted, as long as it is within its elastic range, it will quickly return to its original state, and the impact repeatability is good. In addition, due to its nonlinear characteristics after being impacted, the pulse waveform generated after being impacted is closer to the ideal value, making this type of material more suitable as an impact corrugated pad. The corrugated pad is installed under an impact table with a piston rod in the middle through two semicircular rings. It is used as a waveform generator and can generate better waveforms than wool felt or other materials.

[0042] In another embodiment of the present invention, the polyurethane block is replaced by a rubber block, and the rubber block is formed by curing liquid rubber cast on a metal chassis.

[0043] It should be noted that in the above embodiments and drawings, the projection of the corrugated pad in the vertical direction is circular, but the present invention is not limited to this shape, that is, no matter what shape the projection of the corrugated pad in the vertical direction is, it is within the protection scope of the present invention.

[0044] The above embodiments are only for illustrating the technical concept and features of the utility model, and their purpose is to enable people familiar with this technology to understand the content of the utility model and implement it accordingly. They cannot be used to limit the protection scope of the utility model. All equivalent changes or modifications made according to the spirit of the utility model should be included in the protection scope of the utility model.

Claims

1. A single-rod pull-down semi-sine waveform impact test bench, include: Base; An impact platform, the impact platform is movably disposed above the base, and a sensor for detecting an impact signal is disposed on the impact platform; A connecting rod, the connecting rod is inserted into the base so as to be movable up and down, the upper end of the connecting rod protrudes from the upper end surface of the base and is connected to the bottom center of the impact platform, and the lower end of the connecting rod extends into the base and is connected to a driver for driving the connecting rod to move up and down; A corrugated pad, the corrugated pad is sleeved on the connecting rod and is located between the base and the impact platform, and the corrugated pad is connected to the upper end surface of the base; Features: The corrugated pad is divided into at least two block pads along the radial direction of the connecting rod. The two block pads are distributed on both sides of the connecting rod and are respectively connected to the upper end surface of the base.

2. The single-rod pull-down semi-sine waveform impact test bench according to claim 1, Features: When connected to the upper end surface of the base, the spacing between the facing side surfaces of adjacent block-shaped pads is less than or equal to 0.5 mm.

3. The single-rod pull-down semi-sine waveform impact test bench according to claim 1, Features: The corrugated pad includes a metal chassis and a polyurethane block or a rubber block molded on the metal chassis. A first through hole for the connecting rod to pass through is opened at the center of the metal chassis. A second through hole for the connecting rod to pass through is opened at the center of the polyurethane block or the rubber block. The second through hole is coaxial with the first through hole and has the same aperture as the first through hole.

4. The single-rod pull-down semi-sine waveform impact test bench according to claim 3, Features: The metal chassis is provided with bolt holes for connecting the base, and the bolt holes are multiple and distributed on the outside of the polyurethane block or the rubber block, and adjacent bolt holes are arranged at intervals.

5. The single-rod pull-down semi-sine waveform impact test bench according to claim 3, Features: The upper surface of the metal chassis is provided with a connection structure for enhancing the connection force between the polyurethane block or the rubber block and the metal chassis, the connection structure includes a connection hole group and an annular connection groove, the connection hole group has multiple groups, each of the connection hole groups includes a number of connection holes evenly distributed around the axis of the first through hole, all the connection hole groups are distributed in concentric circles around the axis of the first through hole, the annular connection groove is coaxially arranged on the outside of the first through hole, the annular connection groove has multiple channels and is distributed in concentric circles around the axis of the first through hole.

6. The single-rod pull-down semi-sine waveform impact test bench according to claim 5, Features: The annular connecting grooves and the connecting hole groups are arranged alternately, and the spacing between adjacent annular connecting grooves and the connecting hole groups is equal.

7. The single-rod pull-down semi-sine waveform impact test bench according to claim 5, Features: The connecting hole is a countersunk hole, the countersunk end of the connecting hole is located on the lower surface of the metal chassis, and the cross section of the annular connecting groove is V-shaped.

8. The single-rod pull-down semi-sine waveform impact test bench according to claim 5, Features: The bottom of the polyurethane block or the rubber block is filled in all the annular connecting grooves and all the connecting holes.

9. The single-rod pull-down semi-sine waveform impact test bench according to claim 3, Features: The polyurethane block is formed by solidifying the liquid polyurethane poured on the metal chassis, and the rubber block is formed by solidifying the liquid rubber poured on the metal chassis.

10. The single-rod pull-down semi-sine waveform impact test bench according to claim 3, Features: The lower end of the polyurethane block or the rubber block is cylindrical, and the upper end is a truncated cone with a cone angle of 165-170 degrees.

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