JPH0628675Y2 - Test piece gripping device - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a test piece gripping device, in particular, a test piece gripping device for attaching a flat plate-shaped test piece to a pull rod of a material testing machine for creep test of brittle materials such as ceramics. Regarding the device.

[Prior Art] Generally, strength measurement of brittle materials such as ceramics is performed by a creep test in which a test piece of brittle material is heated at a high temperature in a heating furnace to apply a tensile load.

4 (a) and 4 (b) show JP-A-55-113935.
1 shows a test piece gripping device of a material testing machine for creep test disclosed in Japanese Patent Publication No.
Support holes 3 and 4 and slits 5 and 6 are formed in the two test piece gripping portions 1a and 2a, respectively. The test piece 7 made of ceramic or the like is inserted into the grip portions 1a, 2a through the slits 5, 6, and a pin-shaped interposition member 8 is provided between the upper shoulder portion 7a of the test piece and the inner peripheral surface of the support hole 3. Similarly, similar intervening members 9 are respectively interposed between the lower shoulder portion 7b of the test piece and the inner peripheral surface of the support hole 4, so that the test piece 7 is grasped by the grasping portions 1a and 2a.

This test piece gripping device is configured so that the test piece 7 is formed by the slits 5 and 6.
It is possible to perform the positioning in the thickness direction and prevent the generation of the eccentric load by the interposition members 8 and 9.

FIG. 5 shows a test piece gripping device of the creep test material testing machine disclosed in Japanese Utility Model Laid-Open No. 60-159352, in which the test piece gripping portions 1a of the upper and lower pull rods,
Support holes 3 and 4 and guide grooves 10 and 11 are formed in 2a, respectively. The test piece 7 has support holes 3 and 4 and guide grooves 10 and 1
It is positioned by the stopper pins 12 and 13 after being inserted into the connector 1. The intervening members 8 and 9 are circular support holes 3 and
4 and the slopes of the test piece shoulders 7a and 7b.

This test piece gripping device positions the test piece 7 in the thickness direction by means of stopper pins 12 and 13 and guide groove 1
The test piece 7 is positioned in the width direction by 0 and 11, and the eccentric load is prevented from being generated by the interposition members 8 and 9.

[Problems to be Solved by the Invention] However, in these test piece gripping devices, when the lower intervening member 9 is interposed between the support hole 4 of the lower pull rod grip 2a and the test piece shoulder 7b, The intervening member 9 comes into contact with the shoulder portion 7b of the brittle material test piece, and the test piece is often damaged. Further, in each of the above-described test piece gripping devices, when the thickness of the test piece 7 is different, in order to make the center of the thickness direction of the test piece coincide with the center of the pull rod, the pull rod is adjusted according to the thickness of the test piece. There is also a problem in that the entire grip portion must be replaced.

Therefore, an object of the present invention is to provide a test piece gripping device which allows an intervening member to be interposed without causing damage to the test piece, and does not require replacement of the pull rod gripping portion even for flat plate test pieces of various thicknesses. To provide.

[Means for Solving the Problems] In order to achieve this object, according to the present invention, a supporting hole into which a shoulder portion of a flat plate-shaped test piece is inserted and a guide groove connected to the supporting hole are formed in the front surface. , A pair of upper and lower pull rod grips, each of which has a through hole communicating with the support hole, and a forked tip, which are inserted into the through holes of the upper and lower pull rod grips. A plurality of positioning members for positioning the test piece by sandwiching the test piece shoulder portion with the bifurcated tip, and between the support hole inner peripheral surface of the upper and lower pull rod grips and the test piece shoulder portion. The upper and lower rod-shaped interposing members respectively interposed are U-shaped in cross-section, and through-holes through which the intervening member is inserted are formed at both ends, and are attached to the lower pull rod gripping portion so as to be sandwiched therebetween. A retainer; It is characterized by including.

[Operation] The upper intervening member is placed in the support hole of the upper pull rod gripping part, and the holding tool is attached to the lower pull rod gripping part so that the lower intervening member is inserted into the through hole of the holding tool and the lower intervening member is inserted. Is held by the holder. In this state, the flat plate-shaped test piece is attached to the upper and lower pull rod grips so that the shoulder portion and the adjacent portion thereof are inserted into the upper and lower support holes and the guide groove, respectively. At this time, since the lower intervening member is held by the holder, the lower shoulder portion can be inserted into the lower supporting hole without contacting the lower intervening member. The guide groove positions the test piece in the width direction.

Next, the positioning member is inserted into the through holes of the upper and lower pull rod grips so that the bifurcated tip of the positioning member sandwiches the shoulder of the test piece, and the test piece is positioned in the thickness direction. Thereafter, the upper and lower pull rod grips are separated from each other so that the lower shoulder of the test piece abuts the lower intervening member. These upper and lower intervening members prevent the eccentric load from being generated on the test piece.

If test pieces of different thickness are used, it can be dealt with by replacing the locating member, specifically by replacing the locating member with the gap between the bifurcated tips matching the thickness of the test piece. Yes, there is no need to replace the entire pull rod grip.

[Embodiment] An embodiment of the test piece gripping device according to the present invention will be described below with reference to FIGS. 1 to 3 in which the same parts as those in FIGS. 4 and 5 are designated by the same reference numerals.

In FIGS. 1 and 2, rectangular support holes 3 are provided in the test piece gripping portions 1a and 2a of the upper and lower pull lots 1 and 2, respectively.
4 and guide grooves 10 and 11 connected to this are provided respectively. The plate-shaped test piece 7 has upper and lower shoulders 7a, 7
b is inserted into the support holes 3 and 4, and the shoulder proximity portions 7c and 7d are inserted into the guide grooves 10 and 11, respectively. These guide grooves 10, 11
The width of the test piece is determined such that when the test piece proximity portions 7c and 7d are inserted, the test piece is positioned in the width direction so that the center of the test piece 7 in the width direction substantially coincides with the center of the pull rods 1 and 2. ing.

Further, pin-shaped upper and lower intervening members 8 and 9 are interposed between the upper and lower shoulder portions 7a and 7b of the test piece and the inner peripheral surfaces of the upper and lower support holes 3 and 4, respectively.

Through holes 14 and 15 communicating with the support holes 3 and 4 are bored on both sides of the test piece gripping portions 1a and 2a, respectively, and positioning members 16 and 17 are inserted into these through holes 14 and 15, respectively. As shown in FIG. 3, the positioning members 16 and 17 have bifurcated tips 16a and 17a and a grip portion 16b.
17b, the test piece shoulders 7a, 7b are sandwiched between the forked tips 16a, 17a when inserted into the through holes 14, 15. The positions of the through holes 14 and 15 and the gap D between the bifurcated tips 16a and 17a are the centers of the test pieces 7 in the thickness direction when the test piece shoulders 7a and 7b are sandwiched between the bifurcated tips 16a and 17a. Are pull rods 1 and 2
It is set to almost coincide with the center of.

Holders 18 are attached to the lower pull rod grip portions 2a, and these holders 18 have U-shaped cross sections as clearly shown in FIG. 2, and have through-holes through which the lower intervening member 9 can penetrate. 19 are perforated.

Next, the operation of this embodiment will be described.

The grip of the flat plate-shaped test piece 7 is performed as follows. That is, first, the holder 18 is attached to the lower pull rod grip portion 2a so as to sandwich it, and the lower intervening member 9 is inserted into the through hole 19 of the holder 18. As a result, the lower intervening member 9 is held by the holder 18 while penetrating the lower support hole 4. Thereafter, with the upper intervening member 8 placed in the upper support hole 3, the shoulder portion 7a of the flat plate-shaped test piece 7,
7b is inserted into the support holes 3 and 4, respectively, and the proximity portions 7c and 7d are inserted into the guide grooves 10 and 11, respectively. At this time, since the lower intervening member 9 is held by the holder 18, the lower shoulder portion 7b is inserted into the support hole 4 without coming into contact with the lower intervening member 9, and damage to the test piece 7 due to the contact is prevented. Can be prevented.

After this, the positioning members 16 and 17 are moved to the grip portions 1a and 2a.
Through the through-holes 14 and 15, respectively, and their forked ends 1
6a and 17a sandwich the test piece shoulders 7a and 7b. As a result, the test piece 7 is positioned in the thickness direction. Next, when the upper and lower pull rods 1 and 2 are moved in the directions of the arrows so that the grip portions 1a and 2a are separated from each other, the test piece lower shoulder portion 7b contacts the lower intervening member 9. In this way, the test piece 7 is positioned in the width direction by the guide grooves 10 and 11 and the upper and lower intervening members 8 and 9, and the generation of an eccentric load is prevented.

The positioning members 16 and 17 include the bifurcated tips 16a,
When a plurality of test pieces having different gaps D of 17a are prepared and test pieces having different thicknesses are used, the positioning member having the gap D corresponding to the thickness is selectively used to grip the workpiece. It is possible to deal with test pieces of various thicknesses without exchanging the entire parts 1a and 2a.

In the above embodiment, a pair of positioning members 16 and 17 are provided and attached to both sides of the grips, but they may be attached to only one side of each grip. Further, the interposition member is not limited to the pin-shaped member of the embodiment, but various shapes can be used.

[Effects of the Invention] As is clear from the above description, according to the present invention, since the lower intervening member is held by the holder, the test piece is placed in the lower supporting hole without contacting the lower intervening member. It can be inserted and damage to the test piece can be prevented.
Further, when the test pieces having different thicknesses are used, it is possible to deal with it by exchanging the positioning member, and it is not necessary to replace the entire test piece gripping portion, and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of a test piece gripping device according to the present invention, and FIG. 2 is a side view showing a partial cross-section of the structure when the test piece and the positioning member are removed from the above embodiment. , Third
FIG. 4 is a perspective view showing a positioning member, FIGS. 4 (a) and 4 (b) are front and side views showing a conventional test piece gripping device, and FIG. 5 is another conventional test piece gripping device. FIG. 1 ... upper pull rod, 1a ... upper test piece gripping part, 2
...... Lower pull rod, 2a ...... Lower test piece gripping part, 3,
4 ... Support hole, 8, 9 ... Intervening member, 10, 11 ... Guide groove, 14, 15 ... Through hole, 16, 17 ... Positioning member, 16a, 17a ... Bifurcated tip, 18 ... Holder, 19 ... through hole.

Claims (2)

[Scope of utility model registration request] 1. A test piece gripping device for a material testing device for gripping a flat plate-shaped test piece, wherein a support hole into which a shoulder portion of the flat plate-shaped test piece is inserted and a guide groove continuous with the support hole are formed in the front surface. At the same time, a pair of upper and lower pull rod grips, each of which has a through hole formed in the side portion and a through hole communicating with the support hole,
A plurality of positioning members having a bifurcated tip, which are inserted into the through holes of the upper and lower pull rod grips to position the test piece by sandwiching the test piece shoulder portion with the bifurcated tip; Upper and lower rod-shaped intervening members respectively interposed between the inner peripheral surfaces of the support holes of the upper and lower pull rod gripping portions and the shoulders of the test piece, and a U-shaped cross section, and the intervening members at both ends. And a holder which is attached to the lower pull rod gripping portion so as to sandwich the through hole, and a test piece gripping device. 2. The utility model registration claim, wherein the through holes are formed in both side portions of each pull rod gripping portion, and the positioning member is inserted in each of the through hole portions in both side portions. The test piece gripping device according to item 1.