JPH0140032Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field This invention relates to a material testing machine for testing the material of a test piece, and in particular a gauge for measuring the displacement between the gauges of the test piece. This relates to a displacement meter.

(b) Prior Art When material testing a test piece, a gage displacement meter having a pair of bars and a detector such as a differential transformer is generally used. Typically, this displacement meter has one end of each bar engaged with the test specimen, and a detector is mounted between the other ends of each bar. Further, each bar is connected to be relatively swingable at a position between both ends of the bar. Therefore, when the test piece deforms, each bar relatively swings and displaces following the deformation, and the relative displacement amount of each bar is detected by the detector. Therefore, the displacement between gauges of the test piece can be taken out by each bar and measured by a detector.

In this type of gage displacement meter, a leaf spring has conventionally been interposed between each bar at a position between both ends of the bar. The plates were connected to each other so that they could swing relative to each other. When each bar swings relative to each other, the leaf spring is elastically deformed, thereby absorbing the swing of each bar. However, the elastic deformation of the leaf spring is accompanied by changes in its shape and elasticity. Therefore, especially when the gauge-to-gage displacement of the test piece and the swinging amount of the bar are large, changes in the shape and elasticity of the leaf spring affect the measurement accuracy of the detector, resulting in a problem that the measurement accuracy decreases.

(C) Purpose Therefore, this invention is a gauge-to-gauge displacement meter that extracts the gauge-to-gauge displacement of a test piece using a pair of bars and measures it using a detector such as a differential transformer. This was done with the aim of solving this problem and improving the measurement accuracy of the detector.

(d) Configuration This device has a pair of bars and a detector such as a differential transformer, one end of each of the bars is engaged with a test piece, and the detector is installed between the other ends of each of the bars. , each of the bars is connected to be relatively swingable at a position between both ends of the bar, and the gauge-to-gauge displacement of the test piece is taken out by the bar and measured by the detector. In the gauge distance displacement meter,
Two fulcrum pins are provided between both ends of the bar, each of the fulcrum pins is fixed to one of the bars, and the fulcrum pins are spaced apart from each other within the same plane perpendicular to the length direction of each of the bars. and a compression coil spring is provided around each of the fulcrum pins, and each compression coil spring is placed between the tip of each of the fulcrum pins and a receiving plate fixed to the other bar. and elastically bias each of the fulcrum pins by the receiving plate and each of the compression coil springs, press the tip of each of the fulcrum pins against the other bar, and press the tip of each of the fulcrum pins against the other bar. are in contact with each other at two points, thereby connecting each of the bars so that they can swing relative to each other.

(E) Embodiments Hereinafter, embodiments of this invention will be explained with reference to the drawings.

In the figure, test piece 1 has a circular cross section;
The amount of displacement between the gauges is taken out by a pair of upper and lower bars 2H and 2L, and measured by a differential transformer 3. A differential transformer 3 is installed between the other ends of each bar 2H and 2L. The differential transformer 3 consists of a coil 4 and an iron core 5, and the coil 4 is connected to the upper bar 2H.
The iron core 5 is connected to the lower bar 2L.

In this embodiment, a pair of metal fittings 6H, 6L are fixed to each bar 2H, 2L at a position between both ends of the bars 2H, 2L. Each bar 2H, 2L has each metal fitting 6
It is inserted into the through hole 7 of H, 6L, tightened with a bolt 8, and held by metal fittings 6H, 6L. Two pins 9 are used as fulcrums for the bars 2H and 2L, and the pins 9 are screwed into the lower metal fitting 6L and fixed with nuts 10. Furthermore, two saucers 11 are screwed onto the upper metal fittings 6H and fixed with nuts 12. Each pin 9 has a conical point 13;
The tip 13 is engaged with the dimple of the saucer 11 and is in point contact. Then, the coil spring 14 provided around each pin 9 is engaged with the tip 13 of the pin 9 and the receiving plate 15 of the upper metal fitting 6H.
4, the tip 13 of each pin 9 is pressed against the saucer 11. Thereby, each bar 2H, 2L is connected to be able to swing relative to each other.

In this displacement meter, a pair of upper and lower engaging rods 16H, 16L are connected to the test piece 1 from the opposite side of each bar 2H, 2L.
is engaged with. A pair of upper and lower flanges 18H, 18L are connected to respective engaging rods 16H, 16L by side plates 17, and each bar 2H, 2L is inserted into a through hole 19 of each flange 18H, 18L. Furthermore, two pairs of upper and lower connecting rods 20H,
20L is inserted into the through hole 21 of each metal fitting 6H, 6L and connected to each flange 18H, 18L, and an adjustment nut 22 is screwed onto each connecting rod 20H. A coil spring 23 provided around each connecting rod 20H is engaged with the adjusting nut 22 and the metal fittings 6H, 6L. Therefore, due to the elasticity of the coil spring 23, the test piece 1 is attached to each bar 2.
H, 2L and each engagement rod 16H, 16L. As a result, one end of each bar 2H is fixed to the test piece 1. By operating the adjustment nut 23, the elasticity of the coil spring 23 can be adjusted, and one end of each bar 2H, 2L can be accurately fixed.

In the gage displacement meter of the material testing machine configured as described above, when a load is applied to the test piece 1, the test piece 1 is deformed and a material test can be performed. When the test piece 1 deforms, each bar 2H, 2L follows the deformation and relatively swings and is displaced. Each pin 9 acts as a fulcrum for the bars 2H and 2L, and
Tilt around 1. This allows each bar 2
The fluctuations of H and 2L are absorbed.

When each bar 2H, 2L relatively swings and is displaced, the coil 4 of the differential transformer 3 is connected to the upper bar 2H.
The iron core 5 is displaced integrally with the lower bar 2L. Therefore, the coil 4 and the iron core 5
is relatively displaced, the current in the coil 4 changes, and the relative displacement amount of the bars 2H and 2L is detected. Therefore, the displacement between the gauges of test piece 1 is expressed as bar 2H, 2
It can be taken out by L and measured by the differential transformer 3.

In this displacement meter, when the bars 2H and 2L swing, each pin 9 only tilts, and unlike the conventional leaf spring, there is no change in shape or elasticity. Furthermore, the tip 13 of each pin 9 is connected to the saucer 11.
The pins 9 are engaged with the dimples of the pins 9 and are in only point contact, and each pin 9 tilts smoothly. Therefore,
Each bar 2H, 2L can be smoothly rocked. Therefore, the gauge-to-gage displacement amount of the test piece 1 can be accurately extracted, and the measurement accuracy of the differential transformer 3 can be improved.

(F) Effect As explained above, according to this invention, one end of the pair of bars 2H, 2L engages with the test piece 1, and a detector such as the differential transformer 3 connects to the other end of each bar 2H, 2L. equipped in between. Two fulcrum pins 9 are provided at positions between both ends of the bars 2H and 2L, and each fulcrum pin 9 is fixed to one of the bars 2L. The fulcrum pins 9 extend toward the other bar 2H at intervals in the same plane perpendicular to the length direction of each bar 2H, 2L. Further, a compression coil spring 14 is provided around each fulcrum pin 9, and each compression coil spring 14 is installed between the tip 13 of each fulcrum pin 9 and a receiving plate 15, and the receiving plate 15 is fixed to the other bar 2H. . Therefore, each fulcrum pin 9 is elastically biased by the receiving plate 15 and each compression coil spring 14, and the tip 13 of each fulcrum pin 9 is pressed against the other bar 2H. The bars 2H are in contact at two points, and the bars 2H and 2L are connected to be relatively swingable. Therefore, when a load is applied to the test piece 1 and the test piece 1 is deformed, each bar 2H, 2L follows it and swings around the tip 13 of the fulcrum pin 9. Therefore,
The gauge-to-gage displacement of the test piece 1 can be extracted by each of the bars 2H and 2L and measured by the detector. Furthermore, according to this invention, the tip 13 of each fulcrum pin 9 and the other bar 2H are in contact with each other at only two points, and each bar 2H, 2L can be smoothly swung. It is possible to accurately extract and accurately measure the amount of displacement between gauges.
Moreover, a compression coil spring 14 is provided around each fulcrum pin 9, and each compression coil spring 14
acts directly on the tip 13 of each fulcrum pin 9. Therefore, the tip 13 of each fulcrum pin 9 is surely pressed and held against the other bar 2H, and each bar 2H
H, 2L can be firmly connected, and its reliability is high. Furthermore, each compression coil spring 14 is installed between the tip 13 of each fulcrum pin 9 and the receiving plate 15, and the compression coil spring 14 is not exposed to the outside of the displacement meter. Therefore, when attaching the displacement meter to the test piece 1, and when transporting and storing the displacement meter, the compression coil spring 14 does not hinder the installation, and the workability is good.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing an embodiment of this invention, Fig. 2 is a side view of Fig. 1, and Fig. 3 is a - of Fig. 2.
FIG. 1...Test piece, 2H, 2L...Bar, 3...Differential transformer, 9...Pin, 11...Saucer.

Claims (1)

[Scope of utility model registration request] It has a pair of bars and a detector such as a differential transformer, one end of each of the bars is engaged with a test piece, the detector is installed between the other ends of each of the bars, and the detector is located between both ends of the bars. In a gauge-to-gauge displacement meter in which each of the bars is connected so as to be relatively swingable, and the gauge-to-gauge displacement amount of the test piece is taken out by the bar and measured by the detector, Two fulcrum pins are provided between both ends of the bar, each of the fulcrum pins is fixed to one of the bars, and the fulcrum pins are spaced apart from each other within the same plane perpendicular to the length direction of each of the bars. and a compression coil spring is provided around each of the fulcrum pins, and each of the compression coil springs is placed between the tip of each of the fulcrum pins and a receiving plate fixed to the other bar. and elastically bias each of the fulcrum pins by the receiving plate and each of the compression coil springs, press the tip of each of the fulcrum pins against the other bar, and press the tip of each of the fulcrum pins against the other bar. A gauge-to-gage displacement meter for a material testing machine, characterized in that the bars are connected at two points so that the bars can swing relative to each other.