JP3215301U - Elongation detector - Google Patents

Abstract

It is an object of the present invention to provide an elongation amount detecting device that can be easily attached to a metal material and detect the elongation amount of the metal material by a tensile test. An elongation amount detection device 10 is an elongation amount detection device 10 for detecting an elongation amount in a tensile test of a metal material having ferromagnetism, and is a first magnetized portion that is magnetically attached to a predetermined position of the metal material. 12, a second magnetized part 14 that is magnetized to the metal material at a predetermined distance from the first magnetized part 12, and a first magnetized part 12 and a first And a detecting unit that detects a displacement amount of the distance between the two magnetized portions 14. [Selection] Figure 1

Description

  The present invention relates to an elongation amount detection device.

  2. Description of the Related Art Conventionally, tensile tests are performed in which controlled tension is applied to a sample until it breaks, and mechanical properties such as tensile strength, yield point, elongation, and drawing of the sample are measured. From these measured values, Young's modulus, Poisson's ratio, yield strength, work hardening characteristics, etc. are calculated and used to calculate the strength of the material when designing and developing mechanical products.

  As a technique related to the present invention, for example, in Patent Document 1, first and second front surface side contact members, first and second back surface side contact members, a first connection member, and second Disclosed is a test piece holding mechanism including a connecting member, and a biasing unit that biases the first and second front surface side contact members and the first and second back surface side contact members in directions close to each other. ing.

JP2013-160674A

  It is necessary to measure the amount of elongation of the metal material when the metal material is subjected to a tensile test, but the fastening member is to make the two protrusions for detecting the amount of elongation of the metal material firmly contact the metal material. It was necessary to tighten. If this tightening or loosening operation takes time, the work efficiency may be reduced.

  An object of the present invention is to provide an elongation amount detection device that can be attached to a metal material more easily and detect the elongation amount of the metal material by a tensile test to increase work efficiency.

  An elongation amount detection device according to the present invention is an elongation amount detection device that detects an elongation amount in a tensile test of a metallic material having ferromagnetism, and includes a first magnetized portion that is magnetically attached to a predetermined position of the metal material; A second magnetized part magnetically attached to the metal material at a position different from the predetermined position at a predetermined interval from the first magnetized part, the first magnetized part by the tensile test, and the And a detector for detecting a displacement amount of the distance between the second magnetized portions.

  In the elongation amount detection device according to the present invention, it is preferable that the first magnetized portion and the second magnetized portion include a spherical magnet that is magnetically adhered to the flat portion of the metal material by point contact.

  Further, in the elongation amount detection instrument according to the present invention, the detection unit includes a case unit that houses a magnetic sensor, and a flat plate-like magnetic recording medium unit that is slidable on the magnetic sensor. And the first magnetically attached portion is fixed to the case portion so as to maintain a positional relationship with the magnetic sensor, and the second magnetically attached portion is provided on the magnetic recording medium portion and the magnetic It is preferably movable on the sensor.

  According to the present invention, the first magnetized part and the second magnetized part that can be magnetized to the metal material are provided. Thereby, when a metal material is extended by a tensile test, the amount of elongation can be obtained by detecting the amount of displacement of the distance between the first magnetized portion and the second magnetized portion. As described above, according to the present invention, it is possible to easily attach to a metal material and detect the amount of elongation, thereby improving work efficiency.

It is a figure which shows the elongation amount detection instrument of embodiment which concerns on this invention. It is a top view of the elongation amount detection instrument of embodiment which concerns on this invention. It is a figure which shows a mode that the elongation amount detection instrument of embodiment which concerns on this invention was mounted | worn with the metal material used as the test object of a tension test.

  Embodiments according to the present invention will be described below in detail with reference to the accompanying drawings. Below, the same code | symbol is attached | subjected to the same element in all the drawings, and the overlapping description is abbreviate | omitted. In the description in the text, the symbols described before are used as necessary.

  FIG. 1 is a diagram illustrating an elongation amount detection instrument 10, FIG. 1A is a perspective view of the elongation amount detection instrument 10, and FIG. 1B illustrates a front view of the elongation amount detection instrument 10. ing.

  FIG. 2 is a plan view of the elongation amount detection device 10, FIG. 2 (a) shows the elongation amount detection device 10 in a normal state, and FIG. 2 (b) shows that the magnetic recording medium unit 18 slides. It is a figure which shows a mode that the 2nd magnetizing part 14 moved.

  FIG. 3 is a diagram illustrating a state in which the elongation amount detection instrument 10 is mounted on the metal material 8 to be a test target of the tensile test.

  The elongation amount detection instrument 10 is an instrument for detecting an elongation amount in a tensile test of the metal material 8 having ferromagnetism. The tensile test is a test in which the elongation amount of the metal material 8 is measured by applying a tension so as to extend the metal material 8 in the longitudinal direction using a device (not shown).

The metal material 8 is made of a metal having a ferromagnetic property, such as iron, cobalt, nickel, or gadolinium, and is a flat plate member having a flat surface as shown in FIG.

  The elongation amount detection device 10 includes a first magnetized part 12, a second magnetized part 14, and a detecting part 16. The detection unit 16 has a function of detecting a displacement amount of a distance between the first magnetized part 12 and the second magnetized part 14 by a tensile test. The detection unit 16 includes a case unit 13, a magnetic recording medium unit 18, and a magnetic sensor 20.

  Here, the elongation amount detection instrument 10 will be described as being configured to include the first magnetized portion 12, the second magnetized portion 14, and the detecting portion 16, but the cable portion 26, which will be described later, The calculation display unit 28 may be included in the constituent elements.

  The case part 13 is a member having a substantially concave groove shape when viewed from the front, and is made of an appropriate material, for example, aluminum. The case part 13 accommodates the magnetic sensor 20 inside.

  The magnetic sensor 20 is mounted at a substantially central portion in the groove of the case portion 13. The magnetic sensor 20 has a substantially box shape. A cable portion 26 is connected to one end face of the magnetic sensor 20.

  The magnetic sensor 20 uses a “magnetoresistive element” whose electric resistance changes according to the strength of the magnetic field, and is also called an MR (Magneto Resistance) element.

  Magnetoresistive elements include those using a ferromagnetic thin film and those using a semiconductor thin film, and among the ferromagnetic thin film types, there are AMR elements, GMR elements, and TMR elements. It is assumed that Of course, it is also possible to use an AMR element or a GMR element.

  The magnetic recording medium unit 18 is a flat plate member provided in the case unit 13 so as to be slidable on the magnetic sensor 20. The magnetic recording medium unit 18 is magnetized at N and S poles at equal intervals and is provided with a position signal.

  The width of the magnetic recording medium portion 18 is matched with the groove width of the case portion 13, and the length is set slightly shorter than the case portion 13. The magnetic recording medium unit 18 is slidably mounted on a guide rail provided inside the case unit 13.

  Here, a method for detecting the amount of elongation of the metal material 8 using the magnetic sensor 20 and the magnetic recording medium unit 18 will be described. Specifically, the magnetic field applied to the magnetic sensor 20 changes due to the relative position change between the magnetic recording medium unit 18 and the magnetic sensor 20 that uses a thin film TMR element having a highly sensitive and low distortion pattern arrangement as a detection element. The resistance value changes. Then, the resistance value is read electrically, and the position detection information detected as the change amount can be output via the cable portion 26.

  The case portion 13 is provided with a lid portion 13a that closes the concave opening, and is fixed by a bolt member (not shown). The width of the lid portion 13 is matched with the groove width of the case portion 13, and the length is set slightly shorter than the case portion 13. In addition, the cover part 13a is also a part of the case part 13, and is comprised with a moderate material, for example, aluminum.

The first magnetized portion 12 is provided on one end side of the lid portion 13 a and has a function of being magnetized at a predetermined position of the metal material 8. Since the first magnetized portion 12 is provided on the lid portion 13 a of the case portion 13, it is fixed so as to maintain the positional relationship with the magnetic sensor 20.

  As shown in FIG. 1B, the first magnetized portion 12 has a convex shape in a front view, and a spherical magnet 22 is embedded in the uppermost central portion. The magnet 22 is provided so as to be substantially flush with the uppermost surface.

  Although the magnet 22 is comprised with the permanent magnet, it is preferable that it is comprised with the neodymium magnet with strong magnetizing force, for example.

  The magnetic recording medium portion 18 is inserted between the magnetic sensor 20 and the lid portion 13a, and is attached to the case portion 13 so as to be slidable on the magnetic sensor 20. In the magnetic recording medium portion 18, the second magnetic attachment portion 14 is provided on the other end side of the lid portion 13a in a state in which clogs are put on so as to have the same height as the first magnetic attachment portion 12.

  The second magnetized part 14 has a function of being magnetized to the metal material 8 at a position different from the position where the first magnetized part 12 contacts with a predetermined distance from the first magnetized part 12. The second magnetized part 14 is provided on the magnetic recording medium part 18 and can move on the magnetic sensor 20. As shown in FIG. 1B, the second magnetized portion 14 has a convex shape in a front view, and like the first magnetized portion 12, a spherical magnet is provided at the uppermost central portion. 24 is embedded.

  The magnet 24 is provided so as to be substantially flush with the uppermost surface. Although the magnet 24 is comprised with the permanent magnet, it is preferable that it is comprised with the neodymium magnet with strong magnetizing force, for example. Here, the heights of the uppermost ends of the magnet 22 and the magnet 24 are set to be the same.

  Moreover, since the magnet 22 and the magnet 24 are spherical, when they are brought into contact with the metal material 8, they are point contacts. Therefore, even if the force which moves the magnet 24 by the metal material 8 extending | stretching by a tension test acts, it can move, magnetizing to the metal material 8. FIG.

  As described above, the magnetic recording medium portion 18 is slidably mounted, and the positional relationship between the first magnetic attachment portion 12 and the second magnetic attachment portion 14 is normally shown in FIG. 2A. However, for example, when the metal material 8 is stretched, the distance between the first magnetized portion 12 and the second magnetized portion 14 is increased as shown in FIG.

  The cable unit 26 has a function of transmitting the position detection information output from the magnetic sensor 20 to the calculation display unit 28. The calculation display unit 28 has a function of performing calculation processing on the position detection information detected by the detection unit 16 to obtain the amount of elongation of the metal material 8 and displaying the amount of elongation on the display unit. .

  Then, the effect | action of the elongation amount detection instrument 10 of the said structure is demonstrated. When performing the tensile test of the metal material 8, as shown in FIG. 3, the magnet 22 of the first magnetized part 12 and the magnet 24 of the second magnetized part 14 are magnetized on the metal material 8, respectively. At this time, the positional relationship between the first magnetized part 12 and the second magnetized part 14 is normal, and the distance between the first magnetized part 12 and the second magnetized part 14 is minimum.

  When the tensile test is performed and the metal material 8 is stretched, the second magnetized portion 14 moves in conjunction with the stretch. When the distance between the first magnetized portion 12 and the second magnetized portion 14 changes, the magnetic field applied to the magnetic sensor 20 changes due to the relative position change between the magnetic sensor 20 and the magnetic recording medium portion 18, and the resistance value. Changes.

  The resistance value is electrically read, and the amount of change in the distance between the first magnetized portion 12 and the second magnetized portion 14, that is, the amount of elongation of the metal material 8 is obtained by the calculation display unit 28. In addition, the calculation display unit 28 displays the amount of elongation of the metal material 8 on the screen.

  As described above, when the elongation amount detection instrument 10 is used, the first magnetized portion 12 having the magnet 22 and the second magnetized portion 14 having the magnet 24 can be magnetized only by being brought close to the metal material 8. The elongation amount can be obtained simply by subjecting the metal material 8 to a tensile test. Therefore, it is possible to more easily attach to the metal material 8 and detect the amount of elongation of the metal material 8 by a tensile test, so that there is an advantage of improving work efficiency.

  8 Metal material, 10 Elongation detector, 12 First magnetized part, 13 Case part, 13a Lid part, 14 Magnetized part, 16 Detection part, 18 Magnetic recording medium part, 20 Magnetic sensor, 22 Magnet, 24 Magnet, 26 Cable part, 28 Calculation display part.

Claims (3)

An elongation amount detecting device for detecting an elongation amount in a tensile test of a metallic material having ferromagnetism,
A first magnetized portion that is magnetized at a predetermined position of the metal material;
A second magnetized part that is magnetically attached to the metal material at a position different from the predetermined position at a predetermined interval from the first magnetized part;
An elongation amount detection device comprising: a detection unit configured to detect a displacement amount of a distance between the first magnetized part and the second magnetized part by the tensile test. In the elongation amount detection instrument according to claim 1,
The elongation detecting device according to claim 1, wherein the first magnetized part and the second magnetized part include a spherical magnet that is magnetized in a point contact with the flat part of the metal material. In the elongation amount detection instrument according to claim 1 or 2,
The detector is
A case portion for accommodating the magnetic sensor;
A flat magnetic recording medium portion provided on the case portion so as to be slidable on the magnetic sensor;
The first magnetized part is fixed to the case part so as to maintain a positional relationship with the magnetic sensor,
The elongation detecting instrument, wherein the second magnetized part is provided on the magnetic recording medium part and is movable on the magnetic sensor.