CN104567635A - Device for rapidly detecting coaxial degree of clamps of test machine - Google Patents

Abstract

The invention relates to a device for rapidly detecting the coaxial degree of clamps of a test machine. The device comprises a test rod (1), spherical end heads (2) and sphere clamps, wherein both ends of the test rod (1) are in threaded connection with the spherical end heads (2), and the spherical end heads (2) are mounted in the hollow spherical cavities of the sphere clamps in a clamping manner; each sphere clamp is formed by the butted combination of an upper cavity clamp (4) and a lower cavity clamp (3), a round hole for allowing the test rod (1) to penetrate through is processed in the bottom of each lower cavity clamp (3), and connecting rods which are respectively connected with an upper clamp (5) and a lower clamp (6) of the test machine are respectively arranged at the bottoms of the upper cavity clamps (4); the diameters of the spherical end heads (2) are 1.5-2.5 times of that of the test rod (1), and the spherical centers of the spherical end heads (2) are positioned on the central line of the test rod (1). Through the adoption of the device, the coaxial degree of the upper clamp and the lower clamp of the test machine can be judged only by testing the lead vertical degree of the test rod (1) in different directions. The device has the characteristics of being simple in structure, convenient to use, high in detection speed, and the like.

Description

A kind of device of quick detection experiment machine clamp right alignment

Technical field:

The present invention is a kind of device of quick test grip of testing machine right alignment, belongs to the technical field of structures of product.

Background technology:

Right alignment is extremely important in axial fatigue test.Axially draw-press or draw-pulling fatigue experimental machine installs, debug and just the upper and lower toolholder central axis of warranty test machine can have good verticality afterwards, but cannot ensure, the central axis of fixture is on same straight line.Therefore testing machine needs regularly to check the right alignment of upper and lower fixture whether point-blank namely check the central axis of upper and lower fixture.When the center axis deviation of upper and lower fixture is larger, must adjusts, make upper and lower fixture substantially point-blank to the fixture of testing machine, during with warranty test, sample only bears the effect of axial force, can not be subject to the impact of other direction force.

First be fixedly connected with lower clamp on testing machine by the upper/lower terminal of sample respectively during torture test, then the power system of starting characteristics test machine loads sample.Grip of testing machine can be that sample termination is firmly clamped by fluid pressure type, also can be that screw-type sample termination is screwed in fixture.If the upper and lower chuck of testing machine is not on one wire, then can produce an additional bending moment on sample after testing machine loads causes sample also to bear bending force except bearing axial load simultaneously, when the non-constant of testing machine right alignment, the bending force produced is very large, sample non-axial force is caused to destroy, cause very big error to test, cannot test objective be reached.As can be seen here, ensure in torture test that the right alignment of upper lower clamp is extremely important.

At present, the way of inspection torture test machine clamp right alignment is: adopt a cylindrical sample, sample two ends are fixedly connected with the upper and lower fixture of testing machine respectively, if the upper and lower fixture of testing machine is not point-blank, can produce a bending force on sample, the right alignment of the upper and lower fixture of flexural deformation larger explanation testing machine is poorer.This method is main is the bending deformation quantity will measuring sample, and the process surveying bending deformation quantity is very complicated, usually will take a long time.Specific practice is: on a certain cross section of sample, paste a foil gauge every 90 ° of angles, strain gauge adhesion direction along sample axis direction, totally 4 foil gauges.To the sample two ends difference clamping of foil gauge be posted on the upper and lower chuck of testing machine during verification right alignment, the wire that foil gauge is drawn is connected respectively on the different passages of strainmeter, to sample imposed load, the deflection of 4 foil gauges is read respectively by strainmeter, if the dependent variable reading of 4 foil gauges is substantially identical, then show that testing machine right alignment is better.Dependent variable reading difference as 4 foil gauges is comparatively large, then the upper and lower fixture of testing machine is described not point-blank, its right alignment is bad.Although adopt this mode check test machine right alignment can reach the object of inspection, but Measures compare is complicated, paste foil gauge and the extraction wire of each foil gauge is connected respectively on each passage of strainmeter, sample also will carry out repeatedly reading to the dependent variable of each foil gauge after loading respectively, and then the bending deformation quantity of sample is gone out by the dependent variable change calculations in 4 directions, need just to judge that whether the right alignment of upper and lower fixture is good for a long time.

Summary of the invention

The present invention designs for above-mentioned the deficiencies in the prior art the device providing a kind of quick detection experiment machine clamp right alignment just, its objective is manufacture one easy, device that the right alignment of grip of testing machine can be checked out quickly and easily.

The object of the invention is to be realized by following technical measures:

The device of this kind of quick detection experiment machine clamp right alignment, it is characterized in that: this device comprises check bar (1), spherical termination (2) and sphere fixture, the two ends of check bar (1) are connected with spherical termination (2) by screw thread, spherical termination (2) is installed in the spherical hollow space of sphere fixture hollow, sphere fixture is docked by epicoele fixture (4) and cavity of resorption fixture (3) two parts to combine, the bottom of cavity of resorption fixture (3) is processed with for the circular hole through check bar (1), the bottom of epicoele fixture (4) is provided with and fixture on testing machine (5), the connecting link that lower clamp (6) connects,

The diameter of spherical termination (2) is 1.5 ~ 2.5 times of check bar (1) diameter, and the centre of sphere of spherical termination (2) is positioned on the center line of check bar (1).

The principle of apparatus of the present invention is on-fixed connected modes detection right alignment sample and the mode that is fixedly connected with of upper and lower fixture being become spherical.When the present invention utilizes concavo-convex sphere on-fixed to contact connection, the feature of the normal force of globally radial direction can only be produced, when straight-bar tension, the sphere end that straight-bar is connected with fixture can only produce one can not produce additional bending moment to straight-bar along the power of straight-bar axis direction.Straight-bar two ends are not due to by non axial constraining force, and when straight-bar tension, the sphere at two ends can adjust the contact position with concave spherical surface automatically, and straight-bar is positioned on the centre of sphere line of upper and lower chuck concave spherical surface.When the upper and lower chuck of testing machine on one wire then straight-bar also perpendicular to ground.As above, lower chuck not on the same line then straight-bar two ends automatically adjust angle, make straight-bar be positioned on the line of upper and lower concave sphere's center, no longer perpendicular to ground.As long as the verticality therefore measuring straight-bar just can judge that whether the right alignment of lower chuck on this testing machine is good rapidly, the angle of straight-bar deflection is larger, illustrates that the distance that upper and lower chuck departs from is larger.Thus eliminate the process of the complexity such as subsides foil gauge, line, each passage of debugging strainmeter, survey measurements in the past needed for detection method.And can also judge rapidly that upper and lower fixture has skew in which direction according to the angle excursion of straight-bar, so that adjustment.

Check bar and spherical termination are connected into sample, and the convex spherical of spherical termination and the concave spherical surface of sphere fixture contact with each other, and scribble railway grease between concavo-convex sphere.The upper part of sphere fixture is fixedly connected with grip of testing machine by clamping, is connected with lower part by screw thread.After this device is connected to testing machine, the pulling force that testing machine is less to its applying, makes close contact between concave, convex sphere.When the axis of the upper and lower fixture of testing machine is not on same straight line, convex spherical can rotate, and the straight-bar be attached thereto also can rotate thereupon and straight-bar is positioned on the centre of sphere line of upper and lower sphere fixture.At this moment the verticality detecting straight-bar is only needed can to reflect the right alignment of upper and lower fixture.

For convenience of the verticality measuring straight-bar, check bar bores 2 square holes perpendicular to straight-bar, the direction of two square holes is also mutually vertical, the verticality of straight-bar so only just need can be measured by the levelness of a simple level measurement square hole, thus realize the quick detection of grip of testing machine right alignment, have structure simple, easy to use, detect the advantages such as quick.

Accompanying drawing explanation

This device of Fig. 1 and lower chuck connection diagram on testing machine

Fig. 2 check bar and the connection diagram with spherical termination

The schematic diagram of Fig. 3 sphere fixture upper and lower part

Embodiment

Below with reference to drawings and Examples, apparatus of the present invention are further described:

As shown in accompanying drawing 1 ~ 3, the device of this kind of quick test grip of testing machine right alignment, comprises check bar 1, spherical termination 2 and sphere fixture, and connection and the working method of this device are as follows:

1) two ends of check bar 1 are each passed through the circular hole of the bottom of two cavity of resorption fixtures 3, are then connected with spherical termination 2 respectively by screw thread, the spherical hollow space inside surface of epicoele fixture 4 and cavity of resorption fixture 3 hollow is coated with railway grease;

2) the epicoele fixture 4 of sphere fixture and cavity of resorption fixture 3 are docked combination, the spherical termination 2 at the two ends of check bar 1 is seated in the hollow sphere cavity of epicoele fixture 4 and cavity of resorption fixture 3 formation, then the connecting link arranged bottom epicoele fixture 4 is connected with fixture on testing machine 5, lower clamp 6 respectively;

The diameter of spherical termination 2 is 1.5 ~ 2.5 times of check bar 1 diameter, and the centre of sphere of spherical termination 2 is positioned on the center line of check bar 1;

3) with testing machine, a less pulling force is applied, to eliminate the contact gap of spherical termination 2 in sphere fixture internal cavities to upper and lower sphere fixture.Measure check bar 1 after loading and can judge fixture 5 on testing machine, lower clamp 6 whether on same straight line at the verticality of different directions.Verticality is poorer, shows that the distance departed from is larger.For convenience of measuring the verticality of check bar 1, in check bar 1 central segment along the square hole devising two different directions perpendicular to straight-bar direction, the verticality of straight-bar only need can be measured by the levelness that level meter tests out two square holes.

Claims (1)

1. the device of a quick detection experiment machine clamp right alignment, it is characterized in that: this device comprises check bar (1), spherical termination (2) and sphere fixture, the two ends of check bar (1) are connected with spherical termination (2) by screw thread, spherical termination (2) is installed in the spherical hollow space of sphere fixture hollow, sphere fixture is docked by epicoele fixture (4) and cavity of resorption fixture (3) two parts to combine, the bottom of cavity of resorption fixture (3) is processed with for the circular hole through check bar (1), the bottom of epicoele fixture (4) is provided with and fixture on testing machine (5), the connecting link that lower clamp (6) connects,

The diameter of spherical termination (2) is 1.5 ~ 2.5 times of check bar (1) diameter, and the centre of sphere of spherical termination (2) is positioned on the center line of check bar (1).