CN204286780U - A kind of flexible hinge rotational stiffness experimental apparatus for testing - Google Patents
A kind of flexible hinge rotational stiffness experimental apparatus for testing Download PDFInfo
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- CN204286780U CN204286780U CN201420674931.5U CN201420674931U CN204286780U CN 204286780 U CN204286780 U CN 204286780U CN 201420674931 U CN201420674931 U CN 201420674931U CN 204286780 U CN204286780 U CN 204286780U
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- flexible hinge
- extension board
- firm banking
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Abstract
The utility model provides a kind of flexible hinge rotational stiffness experimental apparatus for testing, comprising: firm banking; Extension board, extension board along firm banking upper surface and perpendicular to firm banking one sidewall extend, one end is fixed on firm banking, and the other end stretches out outside firm banking, and the one end of stretching out arranges pulley; Fixture, fixture is parallel to extension board and is fixed on firm banking; And sensor stand, sensor stand is parallel to extension board and is fixed on firm banking, sensor stand is provided with a sensor; Flexible hinge to be measured extends perpendicular to extension board, and one end is fixed in fixture, and the other end is connected with the crossbeam that horizontal direction extends, and one end of crossbeam is corresponding with sensor, and flexible hinge to be measured arranges cord, and cord is through pulley pendency.The rotational stiffness error that the utility model records can be decreased to less than 10%, more close to actual value, and simple to operation, floor area is little, work efficiency is high, and cost is low, and the scope of application is wider.
Description
Technical field
The utility model relates to a kind of rotational stiffness experimental apparatus for testing, relates more specifically to a kind of flexible hinge rotational stiffness experimental apparatus for testing.
Background technology
Flexible hinge utilizes resilient material microdeformation and from the characteristic of replying, and is used for the mechanical hook-up that connection two solids allowing rotate between the two.Flexible hinge eliminates idle running in transmission process and mechanical friction, can obtain the displacement resolution of superelevation, be widely used in the instrument and meters such as gyroscope, accelerometer, precision balance, STT missile, and obtain unprecedented high precision and stability.But flexible hinge strictly should control the precision of each critical size in process, otherwise just can produce larger error, thus does not reach expection practical function in actual practicality.
Rotational stiffness is an important indicator of flexible hinge design, and it refers to that the ability of elastic deformation resisted by material when being subject to torque.In prior art, the rotational stiffness of flexible hinge calculates mainly through theoretical analysis, mainly comprise the design calculation formula of the flexible hinge that Paros and Weisbord proposes, give when the minimum thickness of flexible hinge is much smaller than reduced mechanical model during cut radius simultaneously; And studies in China personnel are based on the fundamental formular of mechanics and infinitesimal analysis, give the derivation of general flexible hinge rotational stiffness computing formula, and on this basis, draw the design calculation formula of the straight round flexible hinge commonly used; In recent years, along with the development of engineering software ANSYS, the Abaqus etc. based on finite element analysis, the designing and calculating analysis for flexible hinge proposes a kind of numerical analysis means more easily newly.Whether, but these methods still rest on theory stage, whether the result finally drawn is accurate, credible etc. when designing flexible hinge, still needs the checking carrying out great many of experiments.
At present, the rotational stiffness test experiments of flexible hinge is relatively less, such as, the article of the flexible hinge rotational stiffness Analysis &Validation that the people such as Lu Yafei deliver for 2010 on " machinery and electronics " periodical, analyze for straight round shape flexible hinge, calculate on the basis of flexible hinge rotational stiffness method at com-parison and analysis by theoretical formula and finite element software, design flexible hinge rotational stiffness test experiments, carries out experimental verification to result of calculation. propose general ideasand methods and the key problems of the design of flexible hinge rotational stiffness.According to the method in the flexible hinge rotational stiffness Analysis &Validation of Lu Yafei, with simple finite element simulation simulation to power crossbeam applying 30N apart from hinge centres horizontal range 30mm place, produce the torque of 900Nmm, measuring point displacement 31.36 × 10
-4mm.Find that its error is maximum by contrast test and reach 23.9%.The reason of concrete generation error is as follows: 1, power loads on crossbeam and causes beam deformation to produce displacement error; 2, secondly power loads while crossbeam produces torque to flexible hinge and also produces tension, causes flexible hinge to produce stretching strain, therefore produces error to experimental data collection; 3, giving tacit consent to hinge centres in article is flexible hinge torque rotation center, but practical center is on the lower side at hinge centres, therefore in its formula, torque numerical value exists error.Above reason causes producing the rotational stiffness error of calculation and error amount is larger.
Utility model content
The purpose of this utility model is to provide a kind of experimental apparatus for testing of flexible hinge torsional rigidity, thus solves the problem that in prior art, flexible hinge rotational stiffness experimental provision error is larger.
The flexible hinge torsional rigidity experimental apparatus for testing that the utility model provides, this experimental provision comprises: firm banking; Extension board, extension board is that strip is dull and stereotyped, extension board along the upper surface of firm banking and a sidewall perpendicular to firm banking extend, one end of extension board is fixed on firm banking, the other end of extension board stretches out outside firm banking, and one end that extension board stretches out arranges a pulley; Fixture, fixture is parallel to extension board and is fixed on firm banking; And sensor stand, sensor stand is parallel to extension board and is fixed on firm banking, and sensor stand, between extension board and fixture, sensor stand is provided with a sensor; Flexible hinge to be measured, it extends perpendicular to extension board, and one end of flexible hinge to be measured is fixed in fixture, the other end of flexible hinge to be measured is connected with the crossbeam of horizontal direction extension, one end of crossbeam is corresponding with sensor, flexible hinge to be measured is arranged a cord, and cord is through pulley pendency.
Firm banking is provided with matrix mounting hole uniformly, and extension board, fixture and sensor stand are all connected with firm banking by the bolt be installed in matrix mounting hole.
Fixture has the projection of a hollow, and projection arranges a horizontal location bolt and a perpendicular positioning bolt in the horizontal direction respectively with vertical direction, flexible hinge to be measured insert protruding in and fixed by horizontal location bolt and perpendicular positioning bolt.
Sensor is current vortex sensor.
The axes normal of current vortex sensor is in sensor stand.
Crossbeam is strip board, flexible hinge to be measured perpendicular to crossbeam and its end be fixed in the middle part of crossbeam by fixed screw.
Crossbeam is parallel to extension board and sensor stand.
The end of crossbeam and flexible hinge homonymy to be measured arranges a gauge point, gauge point and sensor positioned in alignment.
Flexible hinge to be measured arranges a cutting near crossbeam place, and cutting is parallel to crossbeam.
Two relative semi-cylindrical canyon portions are provided with in the middle part of flexible hinge to be measured.
The utility model is by improving the load mode of experimental provision and power, test the rotational stiffness that the data recorded directly can calculate flexible hinge, the error of calculation of flexible hinge rotational stiffness can be decreased to less than 10%, make the evaluation of rotational stiffness more close to actual value, meanwhile, the data of the experiment provided have more cogency.The utility model is simple to operation, and floor area is little, work efficiency is high, and cost is low, is applicable to common lab practicality and some special occasions tested flexible hinge rotational stiffness.
Accompanying drawing explanation
Fig. 1 is the schematic perspective view of the flexible hinge rotational stiffness experimental apparatus for testing according to a preferred embodiment of the present utility model;
Fig. 2 is the connection diagram of the utility model flexible hinge to be measured used and crossbeam;
Fig. 3 is another schematic diagram that the flexible hinge used according to the utility model is connected with crossbeam;
Fig. 4 is the rotation schematic diagram according to flexible hinge of the present utility model.
Embodiment
Below in conjunction with specific embodiment, the utility model is described further.Should be understood that following examples only for illustration of the utility model but not for limiting scope of the present utility model.
Fig. 1 shows the schematic perspective view of the flexible hinge rotational stiffness experimental apparatus for testing according to a preferred embodiment of the present utility model, and this experimental provision comprises firm banking 10, extension board 20, fixture 30 and sensor stand 40.
Wherein, firm banking 10 is rectangular flat, and it is provided with matrix mounting hole 11 uniformly, and the bolt arranged through this matrix mounting hole 11 can by other parts, and such as extension board 20, fixture 30 and sensor stand 40 are fixed on this firm banking 10.
Extension board 20 is that strip is dull and stereotyped, and its upper surface along firm banking 10 sidewall perpendicular to firm banking 10 extend.One end of this extension board 20 is fixed on firm banking 10 by the bolt at two intervals, and the other end stretches out outside firm banking 10, the one end of stretching out is arranged pulley 21, cord 22 through pulley 21 and in its free end suspension weight.
Fixture 30 is parallel to extension board 20 and is secured by bolts on firm banking 10.Fixture 30 has the projection of a hollow, this projection arranges horizontal location bolt 31 and a perpendicular positioning bolt 32 in the horizontal direction respectively with vertical direction, by regulating this horizontal location bolt 31 and perpendicular positioning bolt 32 to be fixedly clamped to be placed in the flexible hinge to be measured 50 in this hollow boss.
Sensor stand 40 is parallel to extension board 20 and arranges and be fixed on firm banking 10 by two bolts, sensor stand 40 is between extension board 20 and fixture 30, sensor stand 40 is provided with a sensor 41, this sensor 41 is perpendicular to sensor stand 40.
Flexible hinge 50 to be measured extends perpendicular to extension board 20, its one end is inserted the bossing of the hollow of fixture 30 and is fixed respectively by horizontal location bolt 31 and perpendicular positioning bolt 32, the other end is connected with the crossbeam 51 that horizontal direction extends, this crossbeam 51 is parallel to extension board 20 and sensor stand 40, and one end of crossbeam 51 is corresponding with sensor 41.One end that flexible hinge 50 to be measured closes on crossbeam 51 is connected with cord 22, this cord 22 dangles through pulley 21, in test, one end of pendency is for connecting weight thus applying different loads to flexible hinge 50 to be measured, in addition, this cord 22 after suspension weight flexible hinge 50 to be measured with keep level between pulley 21 and parallel with firm banking 10.
Fig. 2 shows the annexation of the utility model flexible hinge to be measured used 50 and crossbeam 51, and wherein, crossbeam 51 is strip board, flexible hinge 50 to be measured perpendicular to crossbeam 51 and its end be fixed in the middle part of crossbeam 51 by fixed screw 52.
Fig. 3 shows the schematic diagram of another angle that the utility model flexible hinge to be measured 50 used is connected with crossbeam 51, wherein, crossbeam 51 arranges a gauge point 53 with the end of flexible hinge 50 homonymy to be measured, this gauge point in experimentation for sensor 41 positioned in alignment (as shown in Figure 1).From Fig. 3 also, flexible hinge 50 to be measured arranges a cutting 54 near crossbeam 51 place, this cutting 54 is parallel to crossbeam 51, for binding cord 22 (as shown in Figure 1) in experimentation, meanwhile, the middle part of flexible hinge 50 to be measured is provided with two relative semi-cylindrical canyon portions 55, width between two depressed parts 55 is T, the width of flexible hinge to be measured is H, and thickness is B, and the radius of two depressed parts 55 is R.
In the embodiment shown in Fig. 1-Fig. 3, the bolt for securing elongated plate 20, fixture 30 and sensor stand 40 is M6 bolt, should be appreciated that the size of bolt and size can be selected according to actual conditions, only exemplarily unrestricted at this.Sensor 41 adopts current vortex sensor, should be appreciated that current vortex sensor is only exemplarily unrestricted at this, and sensor 41 can also select any sensor can measuring change in displacement, such as photoelectric sensor.All devices on firm banking 10 can according to the physical size of flexible hinge large freedom in minor affairs change fixed position relative, and the change of position only needs can realize by being fixed on by bolt in different matrix mounting holes 11.In addition, extension board 20 used in this embodiment, fixture 30 and firm banking 10 are cast iron, and crossbeam and sensor stand are No. 45 steel, should be appreciated that these materials can be other any materials with some strength.
The utility model in use, first one end of flexible hinge 50 to be measured is needed to assemble with crossbeam 51 in advance, then flexible hinge 50 to be measured is loaded in the projection on fixture 30, positioned by the horizontal location bolt 31 on alignment jig and perpendicular positioning bolt 32, make fixture 30 tangent with the edge of the depressed part 55 of flexible hinge 50 to be measured.Then simultaneously according to the adjustment sensor stand 40 of the physical size size reasonable of flexible hinge 50 to be measured and the position of extension board 20, make the widthwise central position of extension board 20 corresponding with the cutting 54 on flexible hinge 50 to be measured, then moving extension board 20 in the longitudinal direction makes pulley 21 and flexible hinge 50 to be measured keep a segment distance, avoids pulley 21 and flexible hinge 50 to be measured to interfere.In addition, the centre-height of sensor 41 should be corresponding with the gauge point 53 on crossbeam 51, and end and the crossbeam 51 of sensor 41 keep 1 ~ 1.25mm spacing.One end of cord 22 is fixed on cutting 54 place of flexible hinge 50 to be measured, the other end of cord 22 passes fixed pulley 21 and hangs a standard quality block, wherein the stagnant hovering of mass is hung, the quality of mass is designated as m, simultaneously, sensor 41 is by NI data acquisition system (DAS) to the change in displacement of Real-Time Monitoring record crossbeam 51 gauge point one end of current vortex data variation, and by Computer display data result, pending data is stable directly can read displacement variable.
As shown in Figure 4, can obtain the displacement variable between crossbeam and sensor to data measured process, displacement variable is designated as △ Z.According to rotational stiffness formula K=M/ θ, wherein M is the torque of directed force F around crossbeam 51 mid point, θ is the corner of flexible hinge 50 to be measured under power F effect, and F=mg, M=mga (a is the vertical distance that point of force application arrives flexible hinge 50 rotation center to be measured), θ=△ θ ≈ tan △ θ=△ Z/L, because the displacement deformation that crossbeam 51 produces is very little, therefore can Approximate Equivalent, error is ignored; Thus the rotational stiffness deriving flexible hinge 50 to be measured in test experiments is
K≈mgLa/△Z。
Carry out rotational stiffness test experiments according to the straight round flexible hinge of the aluminium alloy 6061 of above Computing Principle to three kinds of sizes, three groups of concrete sizes are respectively: first group, B=10mm, H=15mm, R=5mm, T=5mm; Second group, B=10mm, H=15mm, R=6mm, T=3mm; 3rd group, B=15mm, H=15mm, R=6mm, T=3mm.This three components is not numbered 1,2,3.Carry out rotational stiffness test experiments to the 4th group of straight round flexible hinge of No. 45 steel, it is of a size of B=10mm, H=15mm, R=5mm, and the 4th group # is 1# simultaneously.Finally carry out rotational stiffness test experiments to aluminium alloy 6061 hyperbolic-type flexible hinge, it is of a size of B=10mm, H=15mm, R=5mm, and the 5th group # is 2#.The test experiments result of above five groups is as shown in table 1.
Table 1 flexible hinge rotational stiffness experimental data calculated value and finite element stimulation value
(note: X represents hyperbolic-type; Hinge model is expressed as: material-B-H-R-T; Unit: 10
5nmm/rad)
As shown in Table 1, above-mentioned relative error magnitudes is all no more than 10%, consider that above-mentioned source of error is except the error that the utility model experimental provision and method cause, also has the error that test specimen production technology defect causes, and the error produced in theory calculate, therefore the experimental result of this experimental provision can meet requirement of engineering precision, there is higher confidence level.Utilize the utility model also can also can carry out test experiments to other type flexible hinge, such as hyperbolic-type, parabolic type and ellipse etc. simultaneously.
Above-described, be only preferred embodiment of the present utility model, and be not used to limit scope of the present utility model, above-described embodiment of the present utility model can also make a variety of changes.Namely every claims according to the utility model application and description are done simple, equivalence change and modify, and all fall into the claims of the utility model patent.The not detailed description of the utility model be routine techniques content.
Claims (10)
1. a flexible hinge rotational stiffness experimental apparatus for testing, is characterized in that, described experimental provision comprises:
Firm banking;
Extension board, described extension board is that strip is dull and stereotyped, described extension board along firm banking upper surface and perpendicular to firm banking one sidewall extend, one end of described extension board is fixed on described firm banking, the other end of described extension board stretches out outside described firm banking, and one end that described extension board stretches out arranges a pulley;
Fixture, described fixture is parallel to described extension board and is fixed on described firm banking; And
Sensor stand, described sensor stand is parallel to described extension board and is fixed on described firm banking, and described sensor stand, between described extension board and described fixture, described sensor stand is provided with a sensor;
Flexible hinge to be measured, it extends perpendicular to described extension board, one end of described flexible hinge to be measured is fixed in described fixture, the other end of described flexible hinge to be measured is connected with the crossbeam of horizontal direction extension, one end of described crossbeam is corresponding with sensor, described flexible hinge to be measured arranges a cord, and described cord is through described pulley pendency.
2. flexible hinge rotational stiffness experimental apparatus for testing according to claim 1, it is characterized in that, described firm banking is provided with matrix mounting hole uniformly, and described extension board, described fixture and described sensor stand are all connected with described firm banking by the bolt be installed in described matrix mounting hole.
3. flexible hinge rotational stiffness experimental apparatus for testing according to claim 1, it is characterized in that, described fixture has the projection of a hollow, described projection arranges a horizontal location bolt and a perpendicular positioning bolt in the horizontal direction respectively with vertical direction, described flexible hinge to be measured to be inserted in described projection and is fixed by described horizontal location bolt and described perpendicular positioning bolt.
4. flexible hinge rotational stiffness experimental apparatus for testing according to claim 1, is characterized in that, described sensor is current vortex sensor.
5. flexible hinge rotational stiffness experimental apparatus for testing according to claim 4, is characterized in that, the axes normal of described current vortex sensor is in described sensor stand.
6. flexible hinge rotational stiffness experimental apparatus for testing according to claim 1, is characterized in that, described crossbeam is strip board, described flexible hinge to be measured perpendicular to described crossbeam and its end be fixed in the middle part of described crossbeam by fixed screw.
7. flexible hinge rotational stiffness experimental apparatus for testing according to claim 1, is characterized in that, described crossbeam is parallel to described extension board and described sensor stand.
8. flexible hinge rotational stiffness experimental apparatus for testing according to claim 1, is characterized in that, the end of described crossbeam and described flexible hinge homonymy to be measured arranges a gauge point, described gauge point and described sensor positioned in alignment.
9. flexible hinge rotational stiffness experimental apparatus for testing according to claim 1, is characterized in that, described flexible hinge to be measured arranges a cutting near described crossbeam place, and described cutting is parallel to described crossbeam.
10. flexible hinge rotational stiffness experimental apparatus for testing according to claim 1, is characterized in that, is provided with two relative semi-cylindrical canyon portions in the middle part of described flexible hinge to be measured.
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Cited By (7)
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| CN107328649A (en) * | 2017-08-24 | 2017-11-07 | 吉林大学 | The bionical micro-dimension clamping device of Piezoelectric Driving three-jaw based on flexible hinge |
| CN107764547A (en) * | 2017-10-31 | 2018-03-06 | 北京航天计量测试技术研究所 | A kind of spring rates of flexure hinges parameter measuring apparatus |
| CN109100216A (en) * | 2018-09-17 | 2018-12-28 | 江西洪都航空工业集团有限责任公司 | A kind of missile block hanging load tool structure |
| CN109374241A (en) * | 2018-10-29 | 2019-02-22 | 天津大学 | A kind of measuring device of flexible hinge Static stiffness |
| CN110095215A (en) * | 2019-05-31 | 2019-08-06 | 华南理工大学 | A kind of submissive hinge stress measurement device |
| CN110261081A (en) * | 2019-06-06 | 2019-09-20 | 华南理工大学 | A kind of submissive hinge flexibility and running accuracy measuring device based on micro- vision system |
| CN110501125A (en) * | 2019-08-16 | 2019-11-26 | 天津大学 | A kind of flexible support torsion stiffness parameter Simplified Test Equipment and test method |
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2014
- 2014-11-13 CN CN201420674931.5U patent/CN204286780U/en not_active Expired - Fee Related
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107328649A (en) * | 2017-08-24 | 2017-11-07 | 吉林大学 | The bionical micro-dimension clamping device of Piezoelectric Driving three-jaw based on flexible hinge |
| CN107764547A (en) * | 2017-10-31 | 2018-03-06 | 北京航天计量测试技术研究所 | A kind of spring rates of flexure hinges parameter measuring apparatus |
| CN109100216A (en) * | 2018-09-17 | 2018-12-28 | 江西洪都航空工业集团有限责任公司 | A kind of missile block hanging load tool structure |
| CN109100216B (en) * | 2018-09-17 | 2021-05-18 | 江西洪都航空工业集团有限责任公司 | Guided missile slider hanging and loading tool structure |
| CN109374241A (en) * | 2018-10-29 | 2019-02-22 | 天津大学 | A kind of measuring device of flexible hinge Static stiffness |
| CN110095215A (en) * | 2019-05-31 | 2019-08-06 | 华南理工大学 | A kind of submissive hinge stress measurement device |
| CN110261081A (en) * | 2019-06-06 | 2019-09-20 | 华南理工大学 | A kind of submissive hinge flexibility and running accuracy measuring device based on micro- vision system |
| CN110501125A (en) * | 2019-08-16 | 2019-11-26 | 天津大学 | A kind of flexible support torsion stiffness parameter Simplified Test Equipment and test method |
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