JPH0428010Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a displacement meter that measures the displacement that occurs in a test object when a load is applied to the test object.

Prior Art When applying a load to a test piece and measuring its displacement, it is necessary to measure the displacement of the test piece with respect to a certain length, which is the gauge distance. It must be fixed to the gauge set at the location. If the specimen is columnar,
For example, as shown in Utility Model Application Publication No. 59-120408 "Two-axis Displacement Meter Between Gauges", rings are fixed to gauges at two locations on the test specimen using ring fixing needles. The structure is such that a displacement detector detects the displacement of the ring spacing.

Problems to be solved by the invention When fixing the ring to the test specimen using the above method, the ring is carefully installed by visual inspection so that the surface of the ring is perpendicular to the axial direction of the test specimen. It is not necessarily perpendicular to the axial direction of the test specimen, and is often installed slightly tilted. When a displacement test is performed in which a load is applied to the specimen in this state, the specimen undergoes displacement not only in the axial direction but also in a direction perpendicular to the axial direction. Instead of moving perpendicular to the axial direction, it moved in a jumbled manner, leading to a decrease in the reliability of the detected values.

The present invention was devised to solve the above problems, and its purpose is to provide a displacement meter that can detect the amount of displacement with high reliability.

Means for Solving the Problems In order to achieve the above object, the displacement meter according to the present invention includes two rings each having an opening through which a columnar test piece passes, and a ring provided in the ring to fix the ring to the test piece. a distance setting bolt for setting the distance between the rings; and a displacement detector for detecting a displacement in the distance between the two rings; The ring fixing needle is fixed to the ring fixing needle, and the ring fixing needle is inserted into the sleeve, which is made of a hollow cylinder, has a threaded flange formed on the outer periphery of one end, and a sleeve with threads formed on the outer periphery of the other end. , has a guide that guides the ring-fixed needle perpendicular to the axial direction of the test specimen with the ring sandwiched between them, and the overall diameter is approximately Ψ
The guide is assembled into a U-shape, and the guide is formed by bending a band-shaped metal plate into a substantially U-shape, the tip of which is formed into a curved surface, and has a passage hole provided in the central flat part. In addition, the ring fixing needle and the guide are each configured to be crimped in the direction of the side wall of the specimen by separate springs in a state where the pressure can be adjusted, so that when the ring is sandwiched,
The test specimen is supported at three points, including the tip of the guide and the tip of the ring-fixed needle.

Function Since the ring fixing needle provided on the ring is guided perpendicularly to the specimen by the guide, the ring will also be positioned at right angles to the axial direction, and the ring will be fixed in this perpendicular position. It is fixed to the specimen by a needle.

Embodiment FIG. 1 is a plan view showing an embodiment of the present invention. In the figure, in order to fix the ring 31 to the test body 51, the ring 31 has an opening 32 through which the cylindrical test body 51 passes, and fixing means 6 are provided at four locations.
1 is provided. Two rings 31 are fixed to the test specimen 51, and the ring 31b is fixed away from the ring 31a toward the back side of the paper. At two locations facing each other with the specimen 51 in between,
A differential transformer 41 is installed as a displacement detector for detecting displacement of the gap between the rings 31.

Furthermore, distance setting bolts 81 for setting the distance between the two rings 31 are attached to the notches 71 formed at two opposing locations on the ring 31 .

FIG. 2 is an exploded perspective view showing details of the fixing means.

A flange 632 with a thread cut on the outer periphery is formed at one end of the sleeve 63 made of a thin hollow metal tube, and a thread 631 is formed on the outer periphery of the other end up to near the center. Also, approximately in the center,
A groove 634 is formed in which the E-ring 68 is attached. A ring fixing needle 64 having a conical tip and a flange 641 formed near the other end is inserted into the hole 633 of the sleeve 63 . A threaded groove 651 that engages with a thread formed on the flange 632 of the sleeve 63 is carved on the inner periphery of the opening of the knob 65, which is made of a metal cylinder with one end closed. The sleeve 63 has a spring 67 inside that presses the flange 641.
Fixed.

Reference numeral 62 denotes a guide made by bending an elongated metal plate or the like into a substantially U-shape, and has an arc-shaped tip 622 that is rounded and opened outward. Further, a passage hole 621 through which the sleeve 63 passes is formed in the central flat portion of the guide 62.
With the sleeve 63 passing through the passage hole 621 and the spring 66, one of which presses against the guide 62 by being pushed by the flange 632,
Attaching the E-ring 68 to the groove 634 and fixing means 6
1 is assembled into a substantially Ψ shape as a whole.

FIG. 3 shows that the assembled fixing means 61 is attached to the ring 3.
FIG. 1 is a partially omitted external perspective view showing how the device is attached to the device. A cylindrical nut portion 66 is inserted into the attachment hole 33 formed at four locations (some of which are omitted) in the ring 31 from the opening 32 side and is fixed therein.

The nut portion 66 is formed with a flange portion 662 for resisting the force of pulling the ring 31 outward, and a threaded groove 661 carved on the inner periphery is a threaded groove 661 formed on the outer periphery of the sleeve 63 of the fixing means 61. It is designed to mesh with Mt. 631. The guide 62 is the ring 31
The fixing means 61 is the ring 3 which is sandwiched from above and below.
It can be attached to 1.

FIG. 4 is a sectional view taken along the line AB in FIG. 1.

Two rings 31 are attached to the upper and lower sides of the test specimen 51 by fixing means 61, and the differential transformer 4 measures the displacement of the interval between the two rings 31.
1 is provided. The gauge distance H is determined by the lower head surface 82 of the distance setting bolt 81 fixed to the ring 31a with a nut 84, as shown in FIG.
It is set by the distance A between the top surface of the ring 31b and the tip setting surface 83 in contact with it. Also two rings 3
A differential transformer 41 that detects displacement between 1 and 1
is provided.

The operation of the displacement meter of the present invention will be explained below.

The test object 51 is placed in the center of the ring 31b, and the ring 31b is fixed to the test object 51 by rotating the knob 65 on the fixing means 61. At this time, both tips 622 of the guide 62 come into contact with the outer periphery 52 of the test piece 51 at two points in the axial direction, so the ring fixing needle 64 is guided perpendicular to the axial direction of the test piece 51. The force with which the guide 62 guides the ring fixed needle 64 is ensured by the spring 66 pressing the guide 62 against the test specimen 51.

Next, the ring 31a to which the distance setting bolt 81 is attached is placed so that the tip 85 of the distance setting bolt 81 fits into the notch 71 of the ring 31b, and the ring 31a is fixed to the test specimen 51 by the fixing means 61. do. Then, the differential transformer 41 is fixed between the two rings 31, and the distance setting bolt 81 is removed. The ring 31 is pressed by the ring fixing needle 64 by the spring 67 and the guide 62 by the spring 66 against the test specimen 51.
is fixed, the gauge distance H is ensured.
The displacement of the gauge distance H when a load is applied from above and below the test specimen 51 is detected as an electric signal by the differential transformer 41.

Note that the present invention is not limited to the above embodiment, and the force with which the spring 66 presses the guide 62 and the force with which the spring 67 presses the ring fixed needle 64 may be adjusted individually by providing knobs for each. It is.

Effects of the invention In the displacement meter of the invention, a guide is provided in the fixing means to guide the ring fixing needle perpendicularly to the axial direction of the test piece, so that the ring is fixed perpendicularly to the axial direction of the test piece. , it is possible to detect the amount of displacement with high reliability, and since the ring is fixed by both the guide and the ring fixed needle, the fixing force shared by the ring fixed needle is reduced. It is also possible to obtain the effect of preventing the formation of cracks in the test specimen with fewer indentations on the test specimen.

[Brief explanation of drawings]

Figure 1 is a plan view showing one embodiment of the present invention;
The figure is an exploded perspective view showing the details of the fixing means, FIG. 3 is a partially omitted external perspective view showing how the assembled fixing means is attached to the ring, and FIG.
FIG. 5 is a sectional view taken along the line AB in the figure, and a front view showing the distance setting bolt. 31... Ring, 32... Opening, 41... Displacement detector, 51... Test object, 62... Guide, 6
3...Ring fixed needle.

Claims (1)

[Claims for Utility Model Registration] Two rings each having an opening through which a columnar test specimen is passed, a fixing means provided in the rings for fixing the rings to the test specimen, and a means for setting the distance between the rings. It is equipped with a distance setting bolt and a displacement detector that detects the displacement of the distance between the two rings, and the fixing means includes at least a ring fixing needle for fixing the ring to the test specimen, and a hollow cylinder. The needle is inserted through it, and one end has a threaded flange formed on the outer periphery, and the other end has a sleeve with threads formed on the outer periphery. It has a guide that guides the ring-fixed needle, and is assembled in an approximately Ψ-shape as a whole, and the guide is made by bending a band-shaped metal plate into an approximately U-shape, and its tip has a curved surface. It is formed in
It has a passage hole provided in the central flat part, and is configured such that the ring fixing needle and the guide can be crimped in the direction of the side wall of the test specimen by separate springs in a state where the pressure can be adjusted, A displacement meter characterized in that, when a ring is pinched, the test specimen is supported at three points, including the tip of the guide and the tip of the ring fixing needle.