JPH0816642B2 - Parallel leaf spring tension tester - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is a tensile tester for measuring the mechanical properties of materials. Such a tensile tester is used to measure the mechanical properties of various materials in the fields of manufacturing various materials and in the field of research and development of new materials, and also in the inspection of mechanical parts such as springs. Also used for inspection of spring characteristics.

[0002]

2. Description of the Related Art A conventional tensile tester has a pair of chucks located on the same center line and opposed to each other. The pair of chucks cooperate to grip both ends of a test piece, and in this state A large force generated by a hydraulic system or a hydraulic device is transmitted to the chuck via gears or screws and applied to the test piece to perform the test.

[0003]

However, such a conventional tensile testing machine is intended for a test piece which originally requires a certain amount of force for deformation and breakage. Therefore, in such a tensile tester, control of minute force and displacement is inherently limited. This in the first place these conventional tensile testing machine, it and the force generated by the drive unit is large, the transmission mechanism of the displacement-force, for example a tooth wheel, etc. <br/> friction and to feed Rineji, depending on backlash etc. Tagaa is, this is fine
Forces, measurement of the displacement, is because such a cause of disturbance to the control. In addition, the load cell for small loads generally has low rigidity.
In addition, since it deforms in a direction other than the load measuring direction,
A force other than tension, such as bending load, applied to the test piece during hacking
Is easily applied, and the test piece is eccentrically loaded when loaded.
Is easy to operate. Therefore, this bending load and eccentric load are
The development of technology that avoids acting on the specimen is desired.

The present invention has been made in view of the above-mentioned circumstances, and has been made in consideration of the friction and the buckler in the load transmission mechanism.
Disturbance due to sash etc. is eliminated, and force other than tension is applied to the test piece.
It is possible to measure the mechanical properties of extremely small materials and extremely weak materials and the rigidity , strength , etc. of structures, parts, members, products, etc. that have extremely small rigidity . The purpose of the present invention is to provide a tensile tester that can be used.

[0005]

To solve this problem, the parallel leaf spring type tension tester of the present invention is fixed so as to be positioned opposite each other on the same center line and cooperate to grasp the test piece. One chuck member, the other movable chuck member, one parallel plate spring attached to one chuck member, the other parallel plate spring attached to the other chuck member, and one parallel plate A rigid connecting member that connects the spring and the other parallel leaf spring, a non-contact displacement gauge that detects the displacement of the other chuck in a non-contact manner, and a load is applied to the other chuck in the center line direction. It is characterized by including a displacement mechanism and a load cell that detects a load acting on the other chuck in the direction of the center line.

[0006]

When the displacement mechanism pulls the other chuck member via the connecting rod, the other chuck is displaced accordingly.
At this time, the other chuck member is supported by the parallel leaf spring, and the parallel leaf spring, the connecting member, and the other chuck member constitute a rectilinear mechanism, so that the other chuck moves in parallel. At the same time, the relative motion with one of the chuck members also becomes a parallel motion, and after all, the test piece is displaced along the center line while maintaining the position on the center line, so only the axial load acts on the test piece, and the bending and twisting loads act. There is nothing to do. The displacement of the other chuck member is detected by a non-contact displacement type, and the force acting on the other chuck in the direction of the center line is detected by the load cell.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the drawings showing an embodiment. 1 and 2, reference numeral 1 is a tensile tester. The tensile tester 1 has a pair of one chuck member 2a and the other chuck member 2b. The one chuck member 2a and the other chuck member 2b have a center line 3
It is placed facing up. The one chuck member 2a and the other chuck member 2b cooperate to hold the test piece 4. One chuck member 2a is fixed to a fixed block described later and is in a fixed position, and the other chuck member 2b is movable and is displaced relative to one chuck member 2a on the center line 3. One chuck member 2
A and the other chuck member 2b are connected by a leaf spring guide 5.

The leaf spring guide 5 is a pair of parallel leaf springs 6a.
And a parallel leaf spring 6b. The parallel leaf springs 6a and 6b are leaf springs 7a, 7 arranged in parallel, respectively.
b or lines cover to have. Parallel leaf spring 6a and parallel leaf spring 6b
At both ends, the leaf springs 7a and 7b are connected by a connecting frame 8 with a space therebetween, and the parallel plate springs 6a and 6b are connected with the connecting frame 8 at a space. One chuck member 2a is fixed to the center of the parallel leaf spring 6a and also fixed to the tip of the fixed block 11. On the other hand, the other chuck member 2b is connected to the center of the parallel leaf spring 6b, and the movable block 12b.
It is fixed at the tip of. Reflecting plates 13 a and 13 b project from the side surface of the movable block 12. The movable block 12 is connected to a displacement mechanism 15 via a connecting rod 14, and the displacement mechanism 15 has a fixed relationship with the fixed block 11.

A load cell 17 is attached to the displacement mechanism 15, and the load cell 17 detects the load acting on the connecting rod 14 in the direction of the center line 3. The displacement of the movable block 12 is detected by the non-contact displacement gauge 18. The non-contact type displacement gauge 18 detects the displacement of the movable block 12 in a non-contact manner. As such a non-contact type displacement gauge 18, a laser displacement gauge, an eddy current displacement gauge, a capacitance displacement gauge or the like is used. However, a laser displacement meter is used in this embodiment.

The tensile test in the tensile tester 1 thus constructed is carried out as follows. While one chuck member 2a is fixed to the fixed block 11 and the other chuck member 2b is fixed to the movable block 12, both ends of the test piece 4 are fixed to the one chuck member 2a and the other chuck member 2b. The displacement mechanism 15 is operated in this state, through the connecting rod 14 exerts a tensile force on <br/> test piece 4 on the other chuck member 2b. The other chuck member 2
b is pulled by the connecting rod 14 and displaced, but the parallel leaf spring 6
a, each of the leaf springs 7a, 7b and the connecting frame 8及 beauty fixed block 11 of 6b, the movable block 12 constitutes a straight mechanism, therefore, as shown in FIG. 3, one leaf spring 7a, by the elastic deformation of 7b The chuck member 2a and the other chuck member 2b are displaced relative to each other, but they are not displaced in the direction perpendicular to the center line 3, so that no bending load or torsion load acts on the test piece 4 and the parallel to the center line 3. Only tensile loads will work.

Thus, only the mechanical properties of the test piece 4 with respect to the vertical load are tested. The load acting on the test piece 4 is detected by the load cell 17, and the elongation deformation generated in the test piece 4 is detected by detecting the displacement of the movable block 12 by the non-contact type displacement meter 18, but the displacement is not detected. Since the load applied to the test piece 4 by contact is not affected, the mechanical characteristics of the test piece 4 corresponding to only the load can be measured even when the load applied to the test piece 4 is very small. . Minute is as a displacement mechanism 15
An actuator capable of controlling displacement , such as a piezo element or a DC servo motor, can be used, so that a rare deformation can be applied to the test piece 4.

(Experimental Example) FIG. 4 shows data of mechanical properties obtained by performing a tensile test on a stainless fiber having a diameter of 0.1 mm by using the apparatus of the present invention. In the figure, the line a shows the measured load Fm, and the line b shows the load Fs applied to the leaf spring. Therefore, the load Fo applied to the test piece can be obtained by Fo = Fm-Fs.
As is clear from FIG. 4, the tensile tester of the present invention shows that the material test can be effectively performed on a material having a small strength that breaks under a minute load.

[0013]

In the tensile tester of the present invention, the parallel leaf spring is
The test piece is chucked via the parallel leaf spring
Since it is difficult to deform in other directions, use this parallel leaf spring.
The leaf spring guide used in the
Installed between the dowel and the fixed block,
Bending the test piece by placing it in the leaf spring guide of
It is possible to prevent the action of such force. Also, flat
Since elastic deformation of the leaf spring is used, friction and rattling
It is possible to reduce the occurrence of disturbance without causing any noise.
In addition, since parallel leaf springs use elastic deformation,
The reproducibility is very good. Therefore, this spring characteristic
By measuring in advance, you can measure and control minute force.
You can easily prevent it from getting worse. As described above, in the tensile tester of the present invention, minute materials such as fibers, thin films, materials for micromachines, materials for microsensors and the like, materials or materials having low strength, parts or products having low rigidity, which cannot be measured by the conventional material testing machine. It is also possible to measure the mechanical characteristics of, and the strength of a spring having a small spring constant.

[Brief description of drawings]

FIG. 1 is an explanatory plan view of a material testing machine.

FIG. 2 is a vertical cross- sectional configuration explanatory diagram of a material testing machine.

FIG. 3 is an explanatory plan view showing a state of a leaf spring guide when a test piece is broken.

FIG. 4 is a graph showing a tensile test result.

[Explanation of symbols]

 1 Tensile tester 2a One chuck member 2b The other chuck member 3 Center line 4 Test piece 5 Leaf spring guide 6a Parallel leaf spring 6b Parallel leaf spring 7a Leaf spring 7b Leaf spring 8 Connecting frame 11 Fixed block 12 Movable block 13a Reflector 13b reflector 14 connecting rod 15 displacement mechanism 17 load cell 18 non-contact displacement meter

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-6-241969 (JP, A) Actually opened 59-175151 (JP, U) Actually opened 62-20350 (JP, U)

Claims (1)

[Claims] 1. A fixed chuck member, which is positioned on the same center line so as to face each other and can cooperate to grasp a test piece, another movable chuck member, and which is attached to the one chuck member. One parallel plate spring, the other parallel plate spring attached to the other chuck member, and a connecting member having rigidity connecting the one parallel plate spring and the other parallel plate spring. , A non-contact type displacement gauge that detects the displacement of the other chuck in a non-contact manner, a displacement mechanism that applies a load to the other chuck in the center line direction, and a displacement mechanism that acts on the other chuck in the center line direction. A parallel leaf spring tension tester, comprising a load cell for detecting a load.