JPH01223328A - Test piece grasping apparatus - Google Patents

Abstract

PURPOSE:To easily adjust declination and eccentricity with high accuracy, by revolving a declination adjusting plate around the chuck part of an object to be tested to adjust the declination of the object to be tested and moving an eccentricity adjusting plate in a horizontal direction to adjust the eccentricity of the object to be tested. CONSTITUTION:A deflection adjusting plate 13 mounted so as to be revolvable around the chuck part of an object 6 to be tested, a declination adjusting ring 17 capable of controlling the quantity of revolution of the adjusting plate 13 and the chuck main body 22 mounted to the adjusting plate 13 through a load cell 18 are provided. Further, an adjusting screw 23 moving an eccentricity adjusting plate 25 in a horizontal direction in a state freely fixable and horizontally movable with respect to the main body 22 and a chuck mount metal fitting 30 mounting the object 6 to be tested to the adjusting plate 25 in a freely detachable manner are provided. Since the adjusting plate 13 is revolved by a desired angle around the chuck part of the object 6 to be tested by revolving the deflection adjusting ring 17, the deflection of the object 6 to be tested can be freely adjusted. Further, the adjusting plate 25 becomes freely movable in the horizontal direction by screwing or loosening the screw 23 and the eccentricity of the object 6 to be tested can be freely adjusted.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a load testing device for applying a load to a specimen such as a test piece and measuring the tensile strength, etc., and particularly for adjusting the eccentricity and declination of the specimen. The present invention relates to a test specimen gripping device that allows the specimen to hold a specimen.

[Conventional technology]

A gatepost type load testing apparatus shown in FIG. 5 is used as a load testing apparatus for applying a load to a specimen such as a test piece and measuring the tensile strength of the specimen. That is, l is a pair of gateposts fixed to the pedestal 2, 3 is a crosshead fixed between the gateposts 1, 4 is a chuck mount welded to the crosshead 3, and 5 is screwed to the chuck mount 4. combined chuck,
6 is a specimen whose upper end is a test piece held by the chuck 5; 7 is a chuck connected to a hydraulic cylinder 8 such as a hydraulic device installed in the pedestal 2;
The bottom edge of is gripped.

Although not shown, a load cell is incorporated in the chuck mounting base 4.

Next, to explain the operation based on the configuration described above, with both ends of the specimen 6 gripped by the chucks 5 and 7, the hydraulic cylinder piston 8 is
is driven to apply various tensile loads to the specimen 6, and the tensile strength of the specimen 6 is measured.

By the way, in the load test device described above, the chuck 5
, 7 are not aligned, there is a problem that not only a vertical tensile load but also other loads such as torsion act on the specimen 6, making it impossible to conduct an accurate load test.

Therefore, in order to eliminate eccentricity and declination of the specimen, conventionally, as shown in FIG. The joint surface with the second chuck mount 4b is
At the time of manufacturing the test device, each gate post was polished and fixed each time so that the specimen 6 would not be eccentric or declination.

[Problem to be solved by the invention]

By the way, in the conventional test equipment described above, since the cross head 3 is attached to the gate post L, it is inevitable that the eccentricity and declination angle will be deviated depending on the position of the cross head rad 3. Therefore, the position of the cross head is fixed at one point. I was using it.

However, since the specimen 6, which is a test piece, has various shapes and dimensions, it is practically very inconvenient to use the crosshead 3 fixed at one point.

The present invention aims to solve the above-mentioned problems.The purpose of the present invention is to provide a simple structure in which the chuck can be adjusted in the horizontal direction and in the direction of rotation with respect to the vertical plane, and the eccentricity of the specimen can be adjusted. To provide a test specimen gripping device that can easily adjust the declination angle.

[Means to solve the problem]

In order to achieve the above-mentioned object, the specimen gripping device of the present invention has a declination adjustment device attached to the crosshead of the load testing machine so as to be able to rotate around the chuck portion of the specimen, which will be described later. a plate, a declination adjustment ring capable of controlling the amount of rotation of the declination adjustment plate by rotation, a chuck body attached to the declination adjustment plate via a load cell, and fixed to the chuck body. and an eccentric adjustment plate mounted so as to be horizontally movable; and an adjustment screw screwed onto the chuck body to move the eccentric adjustment plate in the horizontal direction when the eccentric adjustment plate is horizontally movable; This is done using a test specimen gripping device equipped with a chuck mounting fitting that detachably attaches the specimen to the eccentric adjustment plate.

[For production]

In the specimen gripping device configured as described above, by rotating the declination adjustment ring, the declination adjustment plate is rotated by a desired angle using the chuck part of the specimen as a fulcrum, so that the declination of the specimen can be freely adjusted. Furthermore, the eccentricity adjustment plate 25 can be moved in the horizontal direction by screwing in or loosening the adjustment screw, so that the eccentricity of the specimen can be adjusted freely.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. Note that in the drawings, the same reference numerals as in FIGS. 5 and 6 above indicate the same parts, and explanations thereof will be omitted.

Reference numeral 11 denotes a fixed member that is positioned by a pin 3a implanted in the crosshead 3 and fixed by means such as welding, and has a curved rubbing surface 11a formed on the lower surface, and 2 facing each other. A recess 11at into which the key 12 is inserted is formed at a location, and a through hole 1 communicating with the through hole 3b of the crosshead 3 is formed in the center of the fixing member.
1b and a part of the outer periphery are formed with an upper cutter 11c, and a stepped portion lid is formed below the upper cutter 11c.

Reference numeral 13 denotes a declination adjusting plate whose upper and lower surfaces are formed on the same plane as the rubbing surface 11a of the fixing member 11, and a key plate 13a on which the key 12 is guided in the diametrical direction of the upper surface.
However, two diagonal guide grooves 13b are also formed on the outer peripheral surface. Further, in the center, an enlarged hole 13c is enlarged upward and communicates with the through hole 11b of the fixing member 11.
is formed (see Figures 3 and 4).

14 has a threaded part 14a at the upper end and a collar part 14b at the lower end.
The supporting rod is formed with a threaded portion 14a at the upper end thereof which penetrates through the enlarged hole 13c of the declination adjustment plate 13 and the through hole 3b of the crosshead 3, and the leaf spring 15
A nut 16 is screwed and fixed therebetween. The upper surface of the flange 14b of the support rod 14 is formed to have the same shape as the lower surface of the declination adjustment plate 13.

Reference numeral 17 is a biasing member whose inner circumferential portion at the upper end coincides with the stepped portion lid of the fixing member 11, and whose tip end of the guide bin 17a protruding from the inner circumferential surface is engaged with the guide groove 13b of the deflection angle adjusting plate 13. A corner adjustment ring has a lower eye mold 17b on the outer peripheral surface of the upper end at a position corresponding to the lower eye mold 11c of the fixing member 11.
is formed.

Then, with the nut 16 loosened, the declination adjustment ring 17 is
When the key groove 13a of the declination adjusting plate 13 is rotated, the key groove 13a is rotated.
2 prevents rotation, when the guide bin 17a moves within the guide groove 13b of the declination adjustment plate 13, the declination adjustment plate 13 is displaced in the direction of the arrow shown in FIG.

Reference numeral 18 denotes a load cell in which an outer ring 18a and an inner ring 18b are connected by a pier 18c. It is fixed to the outer periphery of the lower surface of 13.

21, the upper threaded portion 21a is connected to the inner ring 1 of the load cell 18.
8b and the large diameter part 2 in the center.
A threaded portion 21C is also formed at the lower part via 1b.

Reference numeral 22 denotes a chuck body which is screwed and fixed to the lower screw 21c of the fastening screw 21, and has a recess 22a formed in the center of the lower surface, and a plurality of recesses (for example, one
Three screw insertion holes 22b are formed at 20 degree intervals. Further, a screw support piece 22c is integrally formed on the outer wall corresponding to this screw insertion hole, and an adjustment screw 23 having a locking nut 24 is screwed into this screw support piece 22c, and the tips thereof are respectively described later. The eccentric adjustment plate 25 is in contact with the side surface of the eccentric adjustment plate 25. Note that a spring collar is formed at the lower end of the screw insertion hole 22b.

Reference numeral 25 denotes a hole 25a formed at 120 degree intervals and located between the screw insertion hole 22b of the chuck body 22, and a fall prevention length inserted into the screw insertion hole 22b together with a spring 26. The eccentric adjusting plate has a screw hole into which a screw 27 is screwed, and is fixed to the lower surface of the chuck body 22 by a fixing screw 28 inserted through the hole 25a. Further, a protrusion 25b is formed in the center, and a mounting hole 25c that widens downward is formed in the protrusion 25b.

Then, loosen the three fixing screws 28 and remove the three adjusting screws 2.
3 is screwed in or loosened, the eccentric adjustment plate 25, which is prevented from falling by the long screws 27, will move horizontally into the hole 2.
Move by the size of 5a.

29 is a trapezoidal chuck with 2 minutes υI, and a hole 29 in the center into which the constricted part 6a of the specimen 6, which is a test piece, is fitted.
a is formed. The chuck 29 is inserted into the mounting hole 25c of the eccentric adjustment plate 25 while being fitted into the constricted portion 6a of the specimen 6.

Reference numeral 30 denotes a chuck mounting bracket that comes into contact with the lower surface of the chuck 29, and is fixed to the lower surface of the eccentricity adjusting plate 25 with screws 31, so that the chuck 29 can be attached to the eccentricity adjusting plate 25.
Fixed to. Of course, this chuck attachment fitting 30 has a hole 30a formed therein, through which the specimen 6 is inserted.

The lower end of the specimen 6 is attached to a lower chuck connected to a hydraulic cylinder, as in the conventional case.

Therefore, to explain the operation based on the above configuration, first,
Four strain gauges are attached to the specimen 6 at 90 degree intervals, and the output from the strain gauges is measured by a strain measuring device. After that, a tensile load is applied to the specimen 6 via the lower chuck by a hydraulic cylinder, and the bending component of the specimen 6 is calculated from the amount of strain measured by each strain gauge at this time, and this bending component decreases. Adjust the mounting position of the specimen 6 by rotating the declination adjustment ring 17 with the load removed, and adjust the declination by tightening or loosening the plural adjustment screws 23 and fixing screws 28. This is to adjust the

That is, to adjust the declination angle, loosen the nut 16 and rotate the declination adjustment ring 17. Thereby, the declination adjustment plate 13 is rotated within the primary plane and the angle changes, so that the declination angle can be adjusted. As mentioned above, since the declination angle only changes within the primary plane, when adjusting the declination angle three-dimensionally, the load on the specimen 6 has been removed, so the chuck mounting bracket 30 is By loosening the chuck 29
The specimen 6 becomes rotatable with respect to , .

Further, in adjusting the declination angle, the rotation angle of the declination adjustment ring 17 can be known by looking at the upper scale 11C and the lower scale 17b, and therefore the declination angle can also be determined from this rotation angle. It is.

Next, to adjust the eccentricity, loosen the fixing screw 28 and support the eccentricity adjustment plate 25 with the long screws 27, then tighten or loosen the plural adjustment screws 23 to adjust the eccentricity adjustment plate 25.
Move 5. After the adjustment, the eccentricity can be adjusted by tightening and fixing the locking nut 24.

In the embodiment described above, it is also possible to use a locking microhead for the adjustment screw 23 and read the scale value after locking to check for deviation during operation.

〔Effect of the invention〕

As described above, in the present invention, by rotating the declination adjustment ring, the declination adjustment plate can be rotated using the chuck part of the specimen as a fulcrum, and the declination of the specimen can be adjusted. By tightening or loosening screws, the eccentricity adjusting plate that chucks the specimen moves horizontally and can adjust the eccentricity of the specimen, so it has a relatively simple structure that allows for highly accurate declination and eccentricity. This has the advantage that the adjustment can be easily carried out.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an embodiment of the part for chucking a specimen in the test piece gripping device according to the present invention, Fig. 2 is a central longitudinal sectional view of the same, and Fig. 3 is a partial view of one part of the same. FIG. 4 is a front view of the same as above, FIG. 5 is a front view of a conventional load testing apparatus, and FIG. 6 is a partial cross-sectional view of the part for chucking a specimen in the same as above. 3...Cross head, 6...Specimen, 13...Declination angle adjustment plate, 17...Declination adjustment ring, 1B...Load cell, 22...Chuck body, 23...Adjustment screw, 3
0...Chuck mounting bracket. Patent applicant: Saginomiya Seisakusho Co., Ltd. 13c 5th cause No. 60

Claims (1)

[Scope of Claims] A declination adjusting plate attached to a crosshead in a load testing machine so as to be rotatable about a chuck portion of a specimen to be described later as a fulcrum, and the declination adjusting plate described above being rotated. a chuck body attached to the declination angle adjustment plate via a load cell; an eccentricity adjustment plate fixedly and horizontally movably attached to the chuck body; an adjustment screw that is screwed onto the chuck body and moves the eccentricity adjustment plate in the horizontal direction while the eccentricity adjustment plate is horizontally movable; and a specimen is removably attached to the eccentricity adjustment plate. A specimen gripping device characterized by comprising a chuck mounting bracket and the following.