CN201096684Y

CN201096684Y - Precise clamping device for electronic flexing meter

Info

Publication number: CN201096684Y
Application number: CNU2007200810358U
Authority: CN
Inventors: 王涛; 刘莫峣
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-09-12
Filing date: 2007-09-12
Publication date: 2008-08-06
Anticipated expiration: 2017-09-12

Abstract

The utility model provides a precision clamp device for electronic extensometer in material mechanics field, which is characterized in that: a V-shaped torsion spring and a micro-gap positioning cutter with flexible sleeve tube are arranged on the adjustable locking blocks that are arranged on upper and lower force arms of the electronic extensometer, so as to form three-point clamping force on the sample, the three-point balance force points at the center of sample through the cross section of sample by one-time adjustment, thereby ensuring high stability of static clamping and dynamic clamping of electronic extensometer, so that the relation between the tension stress and the strain is equal to the displacement of the marked distance point at the center of sample. When measuring, sample can perform automatic positioning and clamping. The utility model is applicable to various samples, and can ensure high efficiency measurement and high precision measuring result.

Description

The accurate clamping device of electronic extensometer

Technical field:

Utility model relates to mechanics of materials field tests, particularly the accurate clamping device of electronic extensometer of test stress and strain in the material extending (or compression).

Background technology:

At present, the clamping element that clamping device was suitable for such as the rubber cord of the electronic extensometer that material extending (or contraction) adopts, tension spring, pressure spring are clamped in the knife-blade of extensometer on the sample, under Material Testing Machine application of force condition, clamped blade is with material deformation, with the relation of test sample stress and strain.These clamping elements are because simple in structure, be widely adopted, but the Kinematic Positioning when owing to the static state of this its electronic extensometer of multiple spot clamping attitude and stretching being installed is difficult to consistent, cause the extensometer system to produce additional deformation, increased additional measuring error, reduced the accuracy of measurement result, add the foozle of Material Testing Machine, clamp the malalignment of sample chuck and the malalignment of stretched force-applying direction of motion and clamping direction, sample bending that static clamping produces and the direction of the sample bending of dynamic tensile and inconsistent, the deformation more complicated that sample is produced, because the uncertain flexibility completely that reaches in the position of multiple spot clamping, the active line of the slotted line of blade and pure extension has departed from the distance in sample center during measurement, has deviated from metrological " Abbe measurement principle " and has brought additive error.Have at present and adopt bilateral blade layout can overcome the pure bending distortion that Material Testing Machine produces, but can't eliminate whole additional deformation errors, and this tens(i)ometer is the same with other clamping methods, because mechanical test system is limited by measurement space, manual inconvenience during clamping, efficient is not high yet when carrying out the high frequency time measurement, so need further be improved.

Summary of the invention:

The purpose of this utility model provides a kind of simple in structure, swift and convenient to operate, and can overcome the additive error that produces in electronic extensometer installation and the measuring process, can locate automatically again, clamp and be applicable to the accurate clamping device of electronic extensometer of many kinds and many specifications of sample automatically.

The technical solution of the utility model such as Fig. 1, shown in Figure 2, on the arm of force up and down of electronic extensometer 6, respectively be equipped with and adjust latch segment 1, two screws 2 of adjustment latch segment 1 top employing fixedly screw 2 of microgap knife edge 5 and side fix V-type torsion spring 3, the V-type position of V-type torsion spring 3 is with flexible sleeve 4, the V-type position of the band flexible sleeve 4 of V-type torsion spring 3 and the microgap groove place of microgap knife edge 5 about sample 7 is clamped in, formation clamps 3 power centerings of sample 7, any reacting force of 2 the spring torsion that clamping force contacts with sample 7 from the V-type of V-type torsion spring 3 and the microgap place of microgap knife edge 5, by adjusting latch segment 1, V-type torsion spring 3 is done laterally and vertical quadrature adjustment, to adapt to different sample kind and specification, form 3 equilibrium of forces points and point to sample 7 centers, this moment is the 2 cover three force balance points gauge length that equals to stipulate in the distance of sample center line up and down.The displacement of dynamic tensile (or compression) is equivalent to the displacement of two covers, three power clamping equilibrium point up and down, because the some position of 3 power of two covers is corresponding to three sample buses up and down, the stochastic error that the static state that is applied for the testing machine system clamps and dynamically produces during the application of force, because slotted line essence is the center displacement, its additive error is eliminated.Microgap knife edge 5 microgap points both can have been stablized the kinetic measurement attitude of electronic extensometer 6, again may be at the same description sample of duplicate measurements, round specimen particularly, when directly pushing electronic extensometer 6, " microgap " provides the location and clamps the feel prompting, promptly stops to push the automatic location of realization immediately, clamps automatically, makes each static state clamping attitude in full accord, dynamically the attitude of extensometer is further stable during the application of force, thereby eliminated the static additive error that produces with Kinematic Positioning of installing of extensometer.

The V-type torsion spring 3 of the flexible sleeve 4 that is two cover suits at last is case type U type shapes with the fixed part of electronic extensometer 6 arm of forces, the interval width of U type as shown in Figure 1 and the diameter of flexible sleeve shown in Figure 24 are formed interference fit, this interference fit has limited the axial displacement of V-type clamping point position in the sample direction, has provided simultaneously with material to extend the accurate dynamic location.Do not hinder again sample is radially applied clamping force, a kind of electronic extensometer 6U shape rectangle bending resistance structure of Zu Chenging like this, with 2 of V-type torsion spring 3 contacts displacement that a bit acts on, be equivalent to the displacement of three force balance point and further stablized measuring system by the displacement transducer perception by the arm of force with microgap knife edge 5 microgap places.

The utility model is by tracing to the source at the marking apparatus of specialty to the systematic error structure, and its stability and accuracy draw than other clamp devices outstanding effect.Really shown also that by using it is located automatically, the efficient and convenient performance of automatic clamp operation reaches other clamping devices that high-level efficiency, measurement result high stable, the high precision of the extensive adaptability of different cultivars specification sample and measuring process surmounted existing electronic extensometer, also kept the defencive function that other electronic extensometers come off automatically simultaneously when material is broken.

Description of drawings

Fig. 1. the accurate clamping device structural representation of electronic extensometer;

Fig. 2. the accurate clamping device structure of electronic extensometer schematic top plan view.

Wherein: 1. adjust latch segment; 2. screw; 3.V type torsion spring; 4. flexible sleeve; 5. microgap knife edge; 6. electronic extensometer; 7. sample.

Embodiment:

The utility model is implemented by technique scheme, V-type torsion spring is to adopt the high elastic modulus alloy spring steel wire to make, steel wire diameter is 1.3 millimeters, the microgap knife edge is with the electronics machine cutter of extending, cutting edge place perpendicular to the blade center line opens a groove, about 0.3 millimeter of width, about 1.5 millimeters of the degree of depth, the material of flexible sleeve can adopt the rubber tube of semihard medium-soft or other plastic tube etc., adjusting latch segment is mounted on the arm of force up and down of primary electron extensometer, extensometer itself need not changed, just can realize all kinds of samples are comprised: sheet material, what bar occurred is square, rectangle, circular, the clamping of the different specification size of polygon and profiled cross-section also is adapted to the installation that the material test standard requires various measurement gauge lengths.

Claims

1. the accurate clamping device of an electronic extensometer is the improvement of clamping device fixing on electronic extensometer (6) arm of force, it is characterized in that on the arm of force up and down of electronic extensometer (6), respectively be equipped with and adjust latch segment (1), adjust and to adopt two screws (2) above the latch segment (1) fixedly microgap knife edge (5) and 1 screw in side (2) fix V-type torsion spring (3), the V-type position of V-type torsion spring (3) is with flexible sleeve (4), the V-type position of the band flexible sleeve (4) of V-type torsion spring (3) and the microgap groove place of microgap knife edge (5) about sample (7) is clamped in.