JPS5822121Y2 - material testing machine - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a material testing machine that measures the elongation of a test piece by means of a displacement detection lever attached directly to the test piece when the test piece elongates under load.

Material testing machines are equipped with a means for measuring the elongation of a test piece, but what has traditionally been complicated in testing operations is aligning this elongation measuring means with the reference points of the test piece.

In other words, elongation measurement means have been adopted that are directly attached to the test piece due to its reliable measurement accuracy. Specifically, a detection lever that detects the elongation (displacement) of the test piece is attached to a gauge on the test piece. It has a structure that allows it to be attached.

Such a structure is particularly advantageous when the test piece is made of a material with high elongation, such as rubber or plastic.

However, it is quite difficult to attach such a detection lever to the reference point of the test piece, especially in the case of a structure in which the detection lever is operated along a long extension, due to the relationship with the guide mechanism, it is difficult to attach the detection lever to the gauge point of the test piece. It is difficult to align the displacement detection lever with the gauge because the displacement detection lever cannot be moved to the gauge, and it requires complicated operations and time to accurately match the distance between the upper and lower detection levers to the distance between the gauges.

The present invention aims to provide a material testing machine that solves these drawbacks.

FIG. 1 schematically shows the configuration of the present invention. In the figure, 1 indicates a test piece, which is held at the top and bottom by chucks (not shown) and loaded by a testing machine.

2 and 3 are displacement detection levers, each of which has a fitting 4,
5 to the specimen 1.

Reference numeral 10 denotes a guide rod installed in the testing direction with respect to the machine frame F of the testing machine, and the guide parts 6 and 7 of the displacement detection levers 2 and 3 are engaged with this guide rod 10 to test the displacement detection levers 2 and 3. Guide you to move in the direction.

By the way, the other ends of both displacement detection levers 2 and 3 are connected to a connecting tool 8.
, 9 to separate ropes 11 and 12, respectively.

Each rope 11°12 has a servo motor 23.24
Pulleys 14 and 16 are driven separately by
and is hung on pulleys 13 and 15 above.

17.18 is servo motor 23.24 and pulley 14.1
The potentiometers interposed between the IJs 14 and 6 are operated in conjunction with the rotation of the IJs 14 and 16.

Reference numerals 19 and 20 are gauge distance setting devices that are a feature of this invention, and each has its own potentiometer 17 and 18.
The values are compared with each other.

Each difference signal resulting from this comparison is sent to the servo amplifier 21.
The signal is input to servo motors 23 and 24 via 22.

The two servo motors 23, 24 rotate in response to respective input signals to rotate the pulleys 14, 16.

The amount of rotation of the pulleys 14, 16 is proportional to the magnitude of the difference between the setter 19.20 and the potentiometer 17.18.

Boo! The rotation of J 14 and 16 moves the displacement detection levers 2 and 3 via ropes 11 and 12. In conjunction with the movement of these displacement detection levers 2 and 3, the potentiometer 1
7.18 also operates, and as a result, the values approach the set values of the setters 19 and 20.

Through such control operations, the servo motors 23 and 24 continue to rotate until the difference signal between the setter 19.20 and the potentiometer 17.18 reaches zero, and the displacement detection lever 2
, 3 move.

Then, when the difference signal disappears and the rotation of the servo motors 23 and 24 is stopped, the positions of the displacement detection levers 2 and 3 are brought into alignment with the gauge position and stopped.

The gauge distance is set by the setting devices 19 and 20 using a servo motor 23.24, pulleys 13 to 16, and rope 11.1.
Depending on the configuration of the operating mechanism consisting of 2, the desired value is achieved, and the value is set to an arbitrary value depending on the size of the test piece 1.

In the material testing machine shown in FIG. 1, the elongation of the test piece 1 is measured by the displacement detection levers 2 and 3. after it is set.

In elongation measurement, both displacement detection levers 2 and 3 are attached to the test piece 1 via fixtures 4 and 5, so the elongation (displacement) of the test piece 1 is measured by the displacement detection levers 2 and 3.
It is detected by the detectors 25 and 26 provided at.

The detectors 25 and 26 are constituted by, for example, a differential transformer, and detect when the tips of both displacement detection levers are about to bend due to the elongation of the test piece 1, and emit a signal.

This detection signal is sent to the changeover switch 27 for the control system.
．． 28 to the servo amplifiers 21 and 22, as shown by signals a and b.

That is, when the displacement detection lever has been positioned at the gauge point, the changeover switches 27 and 28 are operated to switch over so that the signals a and b are input.

Then, as mentioned above, the signal a is generated due to the elongation of the test piece 1.

When b is input, the servo motor 23゜2
4 rotates, and both displacement detection levers 2 and 3 move via pulleys 13 to 16 and ropes 11 and 12.

The movement of both displacement detection levers 2 and 3 follows the displacement of the gauge due to the elongation of the test piece 1, and therefore the detectors 25 and 26
If the signal from 2 is erased and the elongation continues, both displacement detection levers 2 and 3 will move accordingly.

The amount of movement of both displacement detection levers is, for example, Boo! j 1
It can be electrically read out from the rotation amounts of 3 and 15.

Not only the rotation amount of pulleys 13 and 15 but also the servo motor 23
．． It is also possible to take out the amount of rotation of the displacement detection levers 2 and 3, and any value corresponding to the amount of movement of the displacement detection levers 2 and 3 may be used.

A signal of this value is designated C in FIG.

That is, FIG. 2 is a block diagram showing the configuration of FIG. 1, and the same reference numerals as in FIG. 1 indicate the same parts.

The material testing machine of the present invention is equipped with a gage distance setting device as described above, and can automatically position the displacement detection lever at the gage position by rotating the servo motor based on the difference signal from the potentiometer. Compared to the conventional test operation in which the displacement detection lever was manually operated, the operation can be performed quickly and with good accuracy.

When the positioning of the displacement detection lever to the gage of the flat test piece (gage point setting) is completed, the elongation of the test piece can be easily measured by switching the switch.

The configuration is simple because the gauge point setting and measurement can be performed using the same servo system.

In addition, in this invention, the method for attaching the displacement detection lever to the component test piece can be freely selected, and the attachment of the displacement detection lever to the test piece and (and) switching of the switch can be performed automatically by remote control. The entire operation can also be fully automated.

[Brief explanation of the drawing]

FIG. 1 is a diagram schematically showing the configuration of a material testing machine according to the present invention, and FIG. 2 is a block diagram thereof. 1... Test piece, 2, 3... Displacement detection lever 11.12... Rope, 13-16...
...Pulley, 17.18...Potentiometer, 19,20...Gage distance setting device, 21,
22... Servo amplifier, 23, 24...
・Servo motor, 25.26...Detector, 27
, 28...... changeover switch.

Claims (1)

[Scope of utility model registration request] A testing machine in which a displacement detection lever is attached to a test piece to measure the elongation of the test piece due to a load includes a motor and an operating mechanism that displaces the displacement detection lever in the test direction relative to the test piece by rotation of the motor. , a potentiometer that is linked to the displacement of the displacement detection lever due to the rotation of the motor, a setting device that sets the gauge distance of the test piece, and a difference signal that compares the setting value of this setting device and the value of the potentiometer. means for outputting, means for detecting displacement of the detection lever due to elongation of the test piece and outputting a corresponding displacement signal, and a changeover switch for selectively inputting the difference signal and the displacement signal to the motor. , by inputting the difference signal to the motor, the displacement detection lever is positioned at a reference point of the test piece via the actuation mechanism, and by switching input of the displacement signal, the displacement detection lever is moved to the test piece via the actuation mechanism. A material testing machine characterized in that the material testing machine is configured to follow the movement of the gauge point due to the elongation of the material.