JPS61164140A - Strain measuring device - Google Patents

Abstract

PURPOSE:To realise simple strain measurement, by fitting a pair of jigs to a sample by holding a plate spring by means of a clip. CONSTITUTION:A pair of jigs 2 has an upper gauge mark 4 which is in contact with a sample 1 and, at the same time, is composed of a stationary section 3 fitted with a dial gauge 5, lower gauge mark 9 which is mounted on the stationary section 3 through a rotation center 7 and contacted with the sample 1, and a movable section 6 equipped with an arm 9 which is in contact with the dial gauge 5. The pair of jigs 2 are coupled with each other at one ends by means of a hinge 10 and, at the same time, plate springs 11 are respectively provided at the other ends of the jigs and, when the plate springs 11 are coupled with each other by holding them by means of a clip 12, the jigs 2 are fitted to the sample 1. When the distance between the gauge marks 4 and 8, length of the arm 9 from the rotation center 7 to the gauge mark 8, and length from the rotation center 7 to the gauge 5 are respectively set to certain values, an appropriate measuring magnification is obtained. Since the sample 1 is fitted to this measuring device under a condition where the sample 1 is held from both sides by holding the plate springs 11 of the pair of jigs 2 by means of the clip 12 in such a way, the sample can be fitted and mounted through a one touch operation and strain measurement can be performed easily and quickly.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an apparatus for measuring strain in a specimen.

(Prior Art) Conventionally, combresometers, wire strain gauges, and the like have been used to measure axial strain, but these have the following problems.

(1) Since there are many contact points with the specimen, the cross-sectional shape of the specimen to be measured is limited to a circular shape.

(2) Since the magnification of deformation is mechanically limited to 2 times, conversion is necessary to determine the strain from the scale of the dial gauge.

(3) If the specimen is destroyed, the dial gauge may also be damaged.

(4) Only the axial strain of the entire specimen can be measured.

(5) Can only be attached to soft specimens such as concrete.

(6) Installation and removal work is complicated.

(Problems to be Solved by the Invention) The present invention solves the problem of attaching and detaching the measuring device as described above.
The purpose of this invention is to provide a measuring device that can easily measure strain on a specimen by solving problems such as various constraints on measurement and ease of handling.

(Means for Solving the Problems) The present invention includes a stationary part having an upper gauge that contacts the specimen and a dial gauge attached thereto, and a stationary part that is rotatably attached to the stationary part and that contacts the specimen. A pair of jigs consisting of a movable part having a lower gauge and an arm that contacts the dial gauge are connected on one side via a hinge, and each side is provided with a leaf spring, and the leaf spring is held between clips. This allows the pair of jigs to be placed on the specimen, and only the gauges of the stationary and movable parts are brought into contact with the specimen, and the jigs are attached using the elasticity of the leaf spring.

(Function) As mentioned above, by holding the leaf spring with clips, the measuring device can be attached to the specimen using the elasticity of the leaf spring, allowing for one-touch attachment and detachment, as well as contact points with the specimen. Since it is only a gauge, it can be installed on specimens with various cross-sectional shapes.Also, by appropriately selecting the length of the arm, the magnification can be increased and the strain can be directly read from the scale of the dial gauge. Furthermore, the strain on both sides of the specimen can be measured independently.

(Example) An embodiment of the present invention is shown in FIGS. 1 to 4.

1 is a specimen, 2 is a pair of jigs, and the same jig 2 is a specimen 1.
It has an upper gauge point 4 in contact with the dial gauge 5.
a fixed part 3 to which a fixed part 3 is attached; a movable part 6 which is rotatably attached to the fixed part 3 through a rotation center 7 and has an arm 9 which contacts a lower gauge point 8 that contacts the specimen l and a dial gauge 5; It consists of

The pair of jigs 2 are connected by a hinge 10 on the negative side and each has a leaf spring 11 on the other side, and is attached to the specimen 1 by sandwiching and connecting the leaf springs 11 with clips 12. It will be done.

The distance Lo between the upper gauge point 4 and the lower gauge point 8 is configured to be freely adjustable, and the length L2 of the arm 9 is also configured to be freely adjustable.

Here, ``distance between gauges Lo, from the rotation center 7 of the arm to the gauge 8
Length L+ from arm rotation center 7 to dial gauge 5
By setting the length L2 up to a certain value, an appropriate measurement magnification can be obtained.

For example, Lo = 15cm, L+ = 1.5cm,
By setting L2 = 10 cm, the ratio between the average strain between the gauge points and the reading of the dial gauge 5 can be made into a 10:1 relationship.

Further, the stationary part 3 is provided with a stopper 13 that restricts rotation of the arm 9 and protects the dial gauge 5.

A pair of jigs as above? Clip the leaf spring 11 of
By sandwiching the measuring device between both sides of the specimen 1, the measuring device can be mounted while being held between both sides of the specimen 1, and since it can be attached and detached with a single touch, attachment and detachment are easy and the time required is shortened, and experimental measurements can be carried out quickly. I can do it. Moreover, it is possible to know the strain of the specimen in real time.

In addition, since the only point of contact with the specimen is the gauge, it is possible to attach it to specimens with various cross sections such as circular and square shapes, and since pressure is applied to the gauge, the material of the specimen can be easily attached. Accurate measurement is possible regardless of whether it is soft or hard.1. or,
Since all of the above pressure is caused by the leaf spring, fine adjustment of the gauge point position can be easily performed.・Furthermore, since the strain on both sides of the specimen can be measured independently, eccentric strain can be determined during central compression experiments, and a stopper is provided to protect the dial gauge during destructive experiments. Since there is no need to remove the measuring device during the measurement, the experimental time can be shortened.

(Effects) As is clear from the above description, the present invention solves the conventional problems, improves the operability and handleability of the measuring device,
Distortion measurements can be easily performed by eliminating various constraints on measurements.

[Brief explanation of the drawing]

Fig. 1 is a side view of a pair of jigs connected and attached to a specimen, seen from the hinge side; Fig. 2 is a side view of the same state, seen from the side connected with a clip; The figure is a cross-sectional view of the vicinity of the upper gauge, and Figure 4 is a cross-sectional view of the vicinity of the lower gauge. 1... Specimen, 2... Jig, 3... Fixed part. 4...Top gauge, 5...Dial gauge. 6...Movable part, 7...Rotation center. 8...Lower gauge, 9...Arm, 10...
Hinge. 11... Leaf spring, 12... Clip. 13...stopper.

Claims (1)

[Scope of Claims] 1. A stationary part having an upper gauge point that contacts the specimen and to which a dial gauge is attached; a lower gauge rotatably attached to the stationary part and contacting the specimen; A pair of jigs consisting of a movable part having an arm that contacts a dial gauge are connected on one side via a hinge, and a leaf spring is provided on the other side.The pair of jigs is assembled by sandwiching the leaf spring with a clip. A strain measuring device characterized in that a tool can be attached to the specimen. 2. The strain measuring device according to claim 1, wherein the distance between the upper and lower gauge points of the pair of jigs is adjustable. 3. Claim 1, characterized in that strain on one or both sides of the specimen can be measured simultaneously with the pair of jigs.
Distortion measuring device described in section. 4. The strain measuring device according to claim 1, wherein the length of the arm is changeable. 5. The strain measuring device according to claim 1, further comprising a stopper for regulating the rotation range of the arm. 6. The strain measuring device according to claim 5, wherein the stopper is provided on the stationary part.