JP2982433B2 - Displacement gauge - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a displacement meter for measuring a displacement generated when a test piece is loaded.

[0002]

2. Description of the Related Art Heretofore, as a displacement meter for measuring the displacement of a test piece, a pair of substantially parallel arms, a leaf spring connecting the base ends of both arms, and an affixed on the leaf spring. A strain gauge type displacement meter having a strain gauge, or a pair of arms independently rotatably provided by a link mechanism, a coil provided at a base end of one arm, and a base end of the other arm There is known a differential transformer type displacement meter including a differential transformer composed of an iron core extending from a portion toward the coil. In any displacement meter, the tip of the arm is locked to a reference point on the test piece, and the arm follows the elongation of the test piece when a tensile force or the like is applied to the test piece, and the arm is opened (rotated). Is measured with a strain gauge or a differential transformer to measure the displacement between the gauge points.

[0003]

However, in the above-described conventional displacement meter, the deflection of the leaf spring caused by the opening movement of the arm is measured by a strain gauge, or the change in the distance between the base ends of the arm caused by the rotation of the arm. Is measured by a differential transformer, and the arm basically performs an arc movement. Therefore, for small displacements, arc movement can be approximated to linear movement, so accurate displacement measurement is possible, but for relatively large displacements, linear movement cannot be approximated, and strain gauges,
There is a problem in that linearity is not established between the amount measured by the differential transformer and the actual displacement between the gauge points, resulting in a decrease in measurement accuracy. In addition, in the case of the strain gauge type displacement meter, it takes time and effort to attach the strain gauge to the leaf spring, and in order to realize the displacement measurement with high accuracy, the skill of attaching the strain gauge is required, and the overall cost is high. There was also a problem that it was a factor of up. On the other hand, in the case of a differential transformer type displacement meter,
There is also a problem that a link mechanism is required to make each arm independently rotatable, and the entire mechanism of the displacement meter becomes complicated.

An object of the present invention is to provide a displacement meter which can perform accurate measurement even for a relatively large displacement and which does not require any skill in assembly with a simple mechanism.

[0005]

The present invention will be described with reference to FIG. 1 showing an embodiment. The present invention is provided so as to be vertically separated from each other along the longitudinal direction of a test piece 1, and the tip is attached to the test piece 1. The present invention is applied to a displacement meter 2 including a pair of edge members 5 and 6 that are pressed and engaged and follow the displacement of the test piece 1 and a detecting unit 11 that detects the displacement of the edge members 5 and 6. The above-mentioned object is achieved by moving both ends provided on each of the edge members 5 and 6 on the left and right sides of the test piece 1 so that the pair of edge members 5 and 6 move in parallel with each other. This is achieved by elastically coupling each other with an elastic coupling member 3c that restricts the above.

[0006]

The edge members 5, 6 are displaced in the longitudinal direction of the test piece following the displacement of the test piece 1. At this time, the edge member 5,
6 so that the edge members 5, 6 move parallel to each other.
Since the left and right ends are connected by the elastic connecting member 3c, the edge members 5 and 6 are displaced following the displacement of the test piece 1 while maintaining a parallel state.

In the means and means for solving the above problems which explain the constitution of the present invention, the drawings of the embodiments are used to make the present invention easy to understand. However, the present invention is not limited to this.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a side view showing an embodiment of a displacement meter according to the present invention, and FIG. 2 is a front view thereof. In these figures, reference numeral 1 denotes a test piece whose displacement amount is to be measured, and the test piece 1 is provided with the displacement meter 2 of the present embodiment.

Reference numeral 3 denotes a frame of the displacement meter 2. The frame 3 connects a pair of frame bodies 3a, 3b arranged vertically along the longitudinal direction of the test piece 1, and connects these frame bodies 3a, 3b. A thin plate-shaped expansion / contraction part 3c is integrally formed. The frame bodies 3a, 3b are provided to extend to the left and right of the test piece 1, and the elastic parts 3c are provided at both left and right ends of the frame bodies 3a, 3b, respectively.
These ends are connected so that the frame bodies 3a and 3b are parallel to each other. Also, the frame body 3
A hollow portion 3d surrounded by the frame main bodies 3a, 3b and the expansion / contraction portion 3c is formed between a, 3b. The hollow portion 3d is formed in a long hole shape when viewed in plan as shown in FIG.

The frame 3 is made of, for example, a metal such as phosphor bronze, and the frame bodies 3a and 3b are vertically parallel along the longitudinal direction of the test piece 1 due to bending of the thin plate-like elastic portion 3c. It is possible to move. On the other hand, as shown in FIG. 1, the frame 3 has a predetermined width in the thickness direction of the test piece 1 as a whole (the left-right direction in FIG. 1). Expansion and contraction and tilting are suppressed.

Reference numerals 5 and 6 denote frame bodies 3a and 3b, respectively.
Edge plates provided at the upper end and the lower end of the edge plate. Edges are formed at the tips 5a, 6a of the edge plates 5, 6,
The support springs 7 and 8 are engaged with the reference points 9 of the test piece 1 respectively.

Reference numeral 10 denotes a magnet fixed to the lower end of the frame main body 3a, and reference numeral 11 denotes a displacement sensor fixed to the upper end of the frame main body 3b to detect a displacement between the magnet 10 and the frame. As the displacement sensor 11, a known displacement sensor such as a magnetic head, a semiconductor magnetic sensor, and an eddy current displacement sensor can be used.

The displacement meter 2 configured as described above can be measured by engaging the tips 5a, 6a of the edge plates 5, 6 with the reference points 9 of the test piece 1 by the support springs 7, 8. In this state, when the test piece 1 is loaded in the tensile direction by a material testing machine or the like, the test piece 1 extends in the longitudinal direction, and follows the edge plate 5, 6 and the frame main bodies 3a, 3a.
b moves up and down. At this time, since the frame bodies 3a and 3b are suppressed from expanding and contracting and tilting in a direction other than the longitudinal direction of the test piece 1 as described above, the frame bodies 3a and 3b are
b moves only in the vertical direction while remaining parallel to each other. The displacement between the frame bodies 3a and 3b is
This displacement sensor 11 detects a displacement between 0 and the displacement sensor 11. Therefore, from the detection signal of the displacement sensor 11, the displacement between the reference points 9 of the test piece 1, that is, the amount of elongation can be measured.

Here, the displacement meter 2 of the present embodiment comprises a test piece 1
The displacement between the edge plates 5 and 6 (and the frame bodies 3a and 3b) that follow and move in parallel with the
Since the displacement (elongation) between the reference points 9 of the test piece 1 is detected by directly measuring the elongation amount, the elongation amount of the test piece 1 is detected from the circular motion of the arm like a conventional displacement meter. On the other hand, linearity between the detection signal of the displacement sensor 11 and the actual displacement between the reference points 9 is established even for a relatively large displacement elongation, and the test piece has a small displacement to a relatively large displacement. The amount of elongation can be measured accurately. In addition, the mechanism is simpler than that of the conventional displacement meter, and a step requiring skill such as attaching a strain gauge is not required, so that cost can be reduced without labor.

In the correspondence between the claims and the embodiment, the edge plates 5 and 6 constitute an edge member, the magnet 10 and the displacement sensor 11 constitute a detecting means, and the extendable portion 3c constitutes an elastic coupling member. .

The details of the displacement meter according to the present invention are not limited to the above-described embodiment, and various modifications are possible. As an example, the external configuration of the displacement meter is not limited to the one in the embodiment. For example, the frame main bodies 3a and 3b and the expansion and contraction portion 3c are configured separately, and a thin metal plate is bent into a long hole shape. The elastic part 3c may be formed by forming the elastic part 3c, or by combining a pair of metal plates bent in a semicircle. Further, the displacement meter may be formed by simply elastically connecting the left and right ends of the edge plate locked to the test piece. Also,
In the above-described embodiment, only the measurement of the elongation direction of the test piece has been described. However, the displacement meter of the present invention can be used for the measurement of the compression direction of the test piece.

[0017]

As described above in detail, according to the present invention, the displacement of the test piece is detected by measuring the displacement of the edge member which moves in parallel with the displacement of the test piece by the detecting means. Therefore, unlike the conventional displacement meter, which detects the displacement of the test piece from the circular motion of the arm, the detection result of the detection means and the actual displacement of the test piece are relatively large even when the displacement is large. Is established, and the elongation of the test piece can be accurately measured from a small displacement to a relatively large displacement. In addition, the mechanism is simpler than that of the conventional displacement meter, and a step requiring skill such as attaching a strain gauge is not required, so that cost can be reduced without labor.

[Brief description of the drawings]

FIG. 1 is a side view showing a displacement meter according to an embodiment of the present invention.

FIG. 2 is a front view showing the displacement meter.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Displacement meter 2 Test piece 3 Frame 3a, 3b Frame main body 3c Expansion / contraction part 3d Cavity part 5, 6 Edge plate 7, 8 Support spring 9 Reference point 10 Magnet 11 Displacement sensor

Claims (1)

(57) [Claims] 1. A pair of edge members which are vertically separated from each other along a deformation direction of a test piece, and whose front ends are pressed and engaged with the test piece to follow the displacement of the test piece. A displacement meter including a detecting unit for detecting displacement, wherein each of the edge members has an end portion located on the left and right across the test piece, and the two end portions are such that the pair of edge members move in parallel with each other. A displacement meter, which is elastically coupled to each other by an elastic coupling member that restrains other movements.